After months of bingeing ER, I am ready. It is time. Here it is! An ER Guest Stars Post.
As we all know, ER was a juggernaut of primetime TV for many years and lasted 15 seasons. (Whether or not it should have died in season 8 along with a certain doctor remains a subject of debate. I am about to embark upon season 9, so I don't yet have an opinion.) Countless actors strolled through the ER over the years, some of them just starting out, some of them famous and thirsting for Emmys. We have child actors who would grow more famous in adulthood, and child actors who would fade into obscurity. I've included a wide range of actors on the fame spectrum, from those who will only be familiar if you've seen the one TV show they starred in, to voice actors who rarely show their faces, to B-list character actors who are in everything, to the fanciest Oscar darlings.
This list is not fully comprehensive, and it's also probably too comprehensive. There are certainly guest stars that I overlooked simply because I haven't seen that one show or movie they are known for. Conversely, I've included people that I was personally excited to see, even though some readers might be like, "Who TF is that???" But I tried to add anyone who seemed noteworthy, even if I wasn't too familiar with their work.
WARNING: This post contains a lot of ER spoilers. It is also image and video heavy!!!!!!!
Shiri Appleby (S1, E1, 1994)
Shiri (of Roswell fame) appeared in the first ever episode of ER as pregnant 13 year old. Interestingly, she would reappear 14 years later to play a different character, Dr. Daria Wade, for nine episodes.
Rosemary Clooney (S1, E3 and E11, 1994)
George Clooney's iconic auntie appeared in two episodes during season one as "Madame X", a woman suffering from dementia who can't talk, but sings. She is identified when a patient recognizes her as famous singer Mary Cavanaugh. Rosemary got an Emmy nom for her performance. (It was her second-to-last ever role.)
Kristen Davis (S1, E13, 1995)
Kristen pops up for one scene to flirt HARD with Doug Ross, who is unimpressed. (Or, rather, he'd love to hop into his filthy bed with her, but he's still pining over Carol Hathaway or...something.)
Milana Vayntrub (S1, E16-18, 1995)
Milana is currently most famous for playing the AT&T lady, but she has been acting for decades. In her first ever role, she played Tatiana, a little girl with AIDS who is abandoned in the ER by her heartless witch of a mother. Carol Hathaway wants to adopt her, but is ultimately deemed unfit due to her past mental health issues.
Bradley Whitford (S1, E19, and S2, E10, 1995)
Bradley has the distinction of appearing in one of the most devastating episodes of ER: Love's Labor Lost. He plays Sean O'Brien, husband of Jodi, who comes into the ER to give birth to their first child. Everything is going fine, until suddenly it all goes tragically wrong.
Debra Jo Rupp (S1, E22, 1995)
Kitty Foreman makes a brief appearance in this episode playing Mrs. Dipple, a woman experiencing a manic episode.
Kathy Griffin (S1, E24, 1995)
Kathy appears briefly in this episode as Dolores Minky, a ranger scout mother who brings her troop in when they all fall disgustingly ill. (Fascinating note: This episode was directed by Quentin Tarantino, who Kathy was dating at the time.)
Lucy Liu (S2, E3-5, 1995)
In one of her early roles, Lucy played Mei-Sun Loew, a mother whose young son is dying of AIDS. Dr. Ross takes a personal interest in the case, encouraging her to seek the most aggressive treatments to buy her son more time, while Dr. Greene advises her to do the opposite, believing the little boy should be made as comfortable as possible. (This storyline is every bit as heartbreaking as it sounds.)
Erik von Detten (S2, E7, 1995)
Ew.
WHO???? You know, that prick Josh from The Princess Diaries. Mia has a puzzling crush on him before she socks him in the nads with a baseball. Anyway, I chose to include him because he has the key role in this episode as the dumbass kid stuck in a flooded culvert who must be gallantly (and I mean GALLANTLY) saved by George Clooney. It is super, duper dramatic.
Adam Goldberg (S2, E9, 1995)
Adam (who would appear soon after in Friends as the creepily troubled Eddie) plays Joshua Shem, a young man suffering from schizophrenia. He calls himself Mr. Sullivan and believes he has important work to do as an architect. After running away from his group care home, refusing to stay with his mother, and not qualifying for a psych hold, the ER releases him to the streets. Carol Hathaway is deeply troubled.
Piper Laurie (S2, E9 and E21, 1995-1996)
Just in case you didn't know, Piper was a super hot 1950s pinup girl.
Piper appears twice in season two as Doug Ross's mother. It isn't much of a role, tbh. They commiserate briefly about Doug's shitty father and that's about it. Wasted opportunity!!!
Jake Lloyd (S2, 1996)
Jake appeared in four episodes during season two, playing Jimmy Sweet, son of Loretta Sweet. Loretta is a regular patient who becomes gravely ill with cervical cancer. Meanwhile her heathen children, Jimmy included, often wreak havoc in the ER. This was Jake's first role.
Nia Long (S2, E15, 1996)
After leaving Fresh Prince (booo!), Nia popped into the ER as Christy, a woman in labor. She was only expecting one baby, but then BOOM, another one starts coming out butt first! Can Dr. Greene deliver the baby successfully despite the evil Dr. Coburn breathing down his neck????
Michael Cudlitz (S2, E16, 1996)
Michael appeared in one scene as Injured Fireman. (Fascinatingly, at least if you're a Walking Dead fan, Jeffrey Dean Morgan would also guest star as an injured fireman a few years later.)
Marg Helgenberger (S2, 1996)
Prior to her CSI fame, Marg appeared as Karen, the girlfriend of Doug Ross's no good father. After daddy Ross disappears, Doug chivalrously takes the woman into his bed for five episodes. It wasn't weird at all, nope! Then he accuses her of forging a prescription for pain killers, they argue, and she is never seen or mentioned again. Probably because she got a better job on a different network. (Working with Jorja Fox, AKA Dr. Maggie Doyle, who would also disappear without explanation.)
Sara Rue (S3, E3, 1996)
Before her big break in Popular and Less Than Perfect, Sara played Jane, a sweet high school student who winds up with gonorrhea after losing her virginity to a total shithead. Doug advises her to avoid guys like that, and as the mayor of Guys Like That, he knows what he's talking about.
Mena Suvari (S3, E4, 1996)
In one of her earliest roles, Mena played Laura-Lee, an angry teen who does not want to have yet another operation. The real purpose of her character is to demonstrate (once again) how Dr. Benton, a Vulcan, is incapable of making an emotional connection with his patients, whereas Carter, a golden retriever, does so effortlessly. (Though I'm amending this to point out that Benton softens substantially as time goes on.)
Kirsten Dunst (S3, 1996-1997)
(This clip is lame, but the few others have terrible quality.)
In season 3, Kiki had a six episode run as Charlie, a 14 year old homeless girl. Doug Ross tries to gallantly rescue her from the streets, but she refuses to become a Hallmark special and just makes his life miserable until she disappears and is never spoken of again.
Corbin Bleu (S3, E9, 1996)
Corbin has a tiny role in this episode as Little Boy. He gets a shot in the butt, administered by Dr. Ross. See?! Notable because this is literally his first role ever. (And because it's a rather hilarious start to a career.)
Clea DuVall (S3, E14, 1997)
In her third ever role, Clea plays Katie, a teenager who just wants to run away with her dying boyfriend. She is actually in two episodes, as Dr. Ross is forced to follow the orders of the teen's mother, who has the legal authority to keep him on a ventilator against his wishes.
Ewan McGregor (and Dennis the Menace) (S3, E15, 1997)
After Trainspotting but before Obi-Wan, Ewan played Duncan Stewart, a jerk who helps his cousin hold up a little grocery store where Carol Hathaway happens to be shopping. Hathaway becomes weirdly emotionally invested in his fate, but when he is gunned down by cops, she shrugs and continues about her day. (JK, I'm just jealous of her resiliency, okay?!) This episode also features Mason Gamble, AKA Dennis the Menace, who later quit acting to become an academic overachiever. He now has a doctorate in engineering.
Heather Matarazzo (S3, E20, 1997)
After Welcome to the Doll House and before The Princess Diaries, Heather swung by the ER for a literal minute to play Alyssa, a majorette with a nasty gash on her leg. Her displeased father would wind up becoming a suspect when a masked assailant beat the crap out of Dr. Greene later in the episode.
Lisa Edelstein, Justina Machado, and Nick Offerman (S4, E1, 1997)
The season four premier had a LOT of guest stars, as you can see!!! Lisa Edelstein (who would eventually costar in House) plays a documentary filmmaker who is doing a piece on the ER for PBS. Justina Nachado plays a woman whose 14 year old brother got beaten with a baseball bat. (She would return in 2009 to play Claudia Diaz, a different character.) And Nick Offerman plays a rocker whose bandmate is the ER patient.
Mariska Hargitay (S4, 1997-1998)
Yes, she still gets the job.
A year before her big break on Law and Order: SPU, Mariska played Cynthia Hooper, a sweet and fragile young woman who bombs her interview to be an ER receptionist when she breaks down crying. But Mark Greene is taken with her and offers her the job (without Carol's approval) and also offers her his bed, and they are in a dysfunctional relationship for 13 episodes.
Clancy Brown (S4, 1997-1998)
Clancy Brown is a prolific voice actor, but he also showed up in seven episodes of ER as Dr. Ellis West. Dr. West is recruited by Kerry Weaver to help improve efficiency in the ER, and he also improves the efficiency in Kerry's bed. But Kerry grows convinced that he is only using her to seal a lucrative deal with the ER, and angrily tells him off in public. He vows that his feelings were genuine, and after delivering a dramatic speech about how sexy Kerry is, he departs to the bottom of the sea and is never seen in the ER again....
Dan Heyada (S4, 1997)
Cher's daddy had a three episode run in season four as Herb Spivak, a lawyer who is rolled into the ER after getting bit by a snake. He ends up becoming Mark's lawyer for a brief spell, in exchange for following him around the ER and putting some of his medical knowledge to good use. (Apparently he returns one more time in 2005.)
Mickey Rooney (S4, E15, 1998)
Mickey Rooney popped by for a minute to play the retired doctor George Bikel. He comes in for an eye exam, tells some amusing anecdotes, and then smells benzene in the ER. It turns out that the ER is benzene contaminated, and chaos follows.
Jonathan Scarfe (S4 and S7)
I'm actually not familiar with this actor, but he's been in a lot of stuff and now stars in the show Van Helsing, so there's got to be SOME people thirsting for him around here. Anyway, he appeared in eight episodes of ER as Chase Carter, John's heroin addicted cousin. After an overdose, he is left brain damaged, and Carter of course blames himself.
Trevor Morgan (S4, 1998)
WHO???? You know, that little shithead bully from The Sixth Sense, and the annoying little kid in Jurassic Park 3. (I actually don't remember if he was annoying, I'm just assuming.) Anyway, before all that he played Scott Anspaugh, the son of head honcho Dr. Anspaugh. Scott has a recurrence of leukemia and is pretty pissed off and hates everyone. But Jeanie Boulet, still learning to cope with her HIV diagnosis, understands him and becomes his friend. But as his condition deteriorates, it is ultimately Jeanie who must tell him it's okay for him to let go. (It's really sad, this show is terrible.)
Eva Mendes (S4, E15, 1998)
In her first TV role, Eva plays Donna, the babysitter of a seriously ill little girl. The above clip is (I believe) her only scene in the episode. (TBH, I did not even recognize her until checking IMDB.)
Taraji P. Henson (S4, E20; S5, E2, 1998)
In her third (and fourth) ever role(s), Taraji appeared in two separate episodes as two different characters. In season four, she played Patrice, Peter Benton's niece. In season five she played Elan, the volatile girlfriend of a volatile patient.
Julie Bowen (S5, 1998-1999)
Julie had a nine episode run as Roxanne Please, a patient who hits it off with Carter and they are a boring couple for awhile. But she is convinced that he has a thing for Lucy Knight, and you really can't blame her, since Carter runs off to have sexual chemistry with Lucy at every opportunity, at one point even making out with her. (As us ER fans know, Carter and Lucy were SUPPOSED to be a couple, but Noah Wyle refused to do the storyline. He claimed it was because Carter would never mess around with a med student, but some suspect he just had a problem with Kellie. By his own admission, he wasn't very nice to her.)
Ashley Johnson (S5, E3-4, 1998)
Come on, YOU KNOW. She played Chrissy Seaver in Growing Pains, and voiced Gretchen in Recess (and in fact has done a lot of voice work over the years, because she naturally sounds like a squeaky cartoon teddy bear.) Here she plays teenager Dana Ellis, who finds out she has cancer in her leg and needs to have it amputated.
Octavia Spencer (S5, E7, 1998)
In one of her earliest roles, Octavia plays Maria Jones, a pregnant woman who fakes abdominal pains so she can find out if her baby is a boy or girl, since she is determined only to have boy babies. ...wait, what?! Anyway, Carol Hathaway, struggling with fertility issues, takes this very personally.
Mare Winningham (S5, E7-11, 1998-1999)
Mare had a four episode run as "Dr. Amanda Lee," a woman Dr. Anspaugh hastily selects as the new chief of staff, mostly because he is desperate to hire anyone but Kerry. He doesn't bother checking her credentials, so he is unaware that she isn't a doctor at all; her name isn't even Amanda. She's just some deranged woman who is pretending to be a doctor (and to be fair, she's a pretty good one.) She also instantly becomes obsessed with Mark Greene, because that man can't catch a break. (Observe those hilarious ornaments. Where did she even get that picture of him?! I died laughing. Luckily, my cat is also a doctor, so I wasn't down long.)
Paul Amandes (S5, E10, 1998)
This one might not mean much to you if you didn't watch Everwood, but I was SUPER excited to see that jerk Dr. Harold Abbot appear as a patient/orchestra musician, David Gardner. David has prostate cancer and thus must have his prostate removed in a surgery set to be performed by Dr. Elizabeth Corday. She convinces him to harvest his sperm before the surgery, and he admits to her (in the above clip) that he had trouble with the task, knowing it would be his final sexual experience, sad face, HINT HINT. Dr. Corday, currently in between love-interests, invites him to "have lunch" with her.
Djimon Hounsou (S5, 1999)
In season 5, Djimon played a janitor named Mobalage Ikabo, who is suffering from PTSD after being tortured in Nigeria. He has mentally blocked out the details of his torture, but he will be deported unless he can remember enough to be granted asylum. Pretty effed up. But Mark Greene opens up about his own assault, which helps Mobalage recover his memories. He appeared in six episodes.
Akosua Busia (S5, 1999)
In a four episode run, Akosua, best known as Nettie from The Color Purple, played Mobalage's wife, Kubby. Kubby is also traumatized by some horrific things that happened to her in Nigeria. This was one of Akosua's last TV/film roles, but she still makes music and recently starred alongside Lupita Nyong'o in the Broadway show, Eclipsed. ALSO, she is literally a princess from Ghana.
Marlee Matlin (S5, E14, 1999)
Marlee had one scene in this episode, playing Benton's ASL instructor.
Anna Gunn (S5, E18, 1999)
Anna appeared briefly in this episode as the lawyer for Mobalage Ikabo, an ER janitor who is facing deportation.
Rebecca De Mornay (S6, E 1-5, 1999)
<Rebecca had a five episode run as Elaine Nichols, the hot ex-wife of Carter's uncle or cousin or something. When she comes into the ER with a minor injury, Carter drools profusely and she permits it and they wind up in bed. But then he snoops around and finds out she has breast cancer and is scheduled to have a mastectomy. She is angry that he found out, and tells him hundreds of times to leave her alone, but he still appears at her doorway, insisting on ~comforting~ her. Then she goes off to Europe and is never seen again.
Alan Alda (S6, 1999)
Alan Alda had a five episode arc in season 6 as Dr. Gabriel Lawrence, a legend in his field and Kerry Weaver's college mentor. His story quickly descends into tragedy when his new colleagues notice that he is showing the early signs of Alzheimer's. Alda was nominated for an Emmy but lost to some other guy.
Emile Hirsch (S6, E7 and E9)
Before he was assaulting women in public and blaming it on drugs, Emile appeared in two episodes as Chad Kottmeier, an alcoholic teen.
Gabrielle Union (S6, E10, 2000)
Before Bring It On, but after She's All That (and years of TV acting), ageless 27 year old vampire Gabrielle played high schooler Tamara Davis, who gets injured in a car accident. Dr. Finch suspects she wanted to injure herself, to take a break from her grueling schedule as a student athlete.
Chris Marquette (S6, E12, 2000)
Before he was Joan of Arcadia's boyfriend and Bill Hader's military buddy in Barry, Chris played Marty, a teen who is injecting growth hormones in his desperation to grow taller. (People are also mad at Marty for pushing a kid in a wheelchair down the stairs, until they find out the kid is Shia LaBeouf.)
Anton Yelchin (S6, E13, 2000)
In his first ever role, cute little moppet Anton appeared as Robbie Edelstein, whose parents are killed in a car accident. It is very upsetting.
Dakota Fanning (S6, E19, 2000)
(This clip features the nameless male nurse who looks a bit like Billy Ray Cyrus.)
In her first ever role, Dakota plays Delia, a little girl who is brought in after a car accident and finds out her leukemia is back. She only has one scene; the real drama involves her half sister, who wants to be tested as a bone marrow candidate, but her vindictive mother forbids it. (The mom is still mad at her ex-hubby, Dakota's dad. Can Abby Lockhart convince her to stop being an evil harpy and consent to the tests?!)
Wentworth Miller (S7, E1, 2000)
In his third ever role, Wentworth plays Mike, a football player who is injured during a Big Game. He is such a popular student and player, a riot eventually breaks out between the two teams, flooding the ER with injured players and cheerleaders. (Note: Wentworth, who was 28 at the time, played a 17 year old high school student.)
Christine Cavanaugh (S7, E3, 2000)
Oh, you know her! At least you know her voice. She played Chuckie in Rugrats, Gosalyn Waddlemeyer-Mallard in Darkwing Duck, Dexter in Dexter's Laboratory, and Babe the Pig. In this episode, her whole self appeared as Gloria, a woman overwhelmed by her monstrous kids and grandkids. It turns out a warrant is out for her arrest (due to writing bad checks), so Kerry Weaver sneaks her out of the ER. Sadly, this would be one of Christine's final roles. She stopped acting and voice acting in 2003, and died of undisclosed causes in 2014. She was only 51.
Sally Field (S7, 2000-2001)
In season seven, Sally Field played Maggie, Abby Lockhart's bipolar mother. She shows up at the ER one day to wreak havoc on Abby's life, and continues to require constant intervention before eventually (maybe) stabilizing. Sally would return in seasons 9 and 13 for a total of twelve episodes. She won two Emmys for the role.
Daveigh Chase (S7, E9, 2000)
LOL I couldn't find a pic or video from the episode, so a Samara image was obviously the only acceptable alternative.
In one of her earliest roles, Daveigh plays Taylor, a little girl who is sick and tired of donating blood to her cancer stricken sister. Dr. Benton finds her hiding in a closet and soon discovers that she was conceived purely to keep her sister alive. (Sound familiar?! The identically plotted novel, My Sister's Keeper, was published four years later.) Anyway, it's no wonder that Taylor became Samara and started killing people. (She turned out not-so-great IRL, too.)
Jared Padalecki and Jim Belushi (S7, E10, 2001)
In this episode, Jared and Jim play a father and son who get in a car accident. The episode is mostly from Jim's POV -- literally, as the camera shows what he sees in several disorienting shots from the gurney. (This fancy episode was directed by David Nutter, who went on to direct a few war movies, and several episodes of Game of Thrones.) This was Jared's third ever role.
James Cromwell (S7, 2001)
In a four episode arc, James played Bishop Stewart, a stubborn old goat who tortures Dr. Kovac by refusing to properly treat his advanced lupus. But before he dies, can he help Luka face his tragic past (and perhaps even mend his shattered faith)???
Josh Peck (S7, E13, 2001)
Josh (of Drake and Josh, and he played a moron on Fuller House) appeared as Nick Stevens, a young teen who needs a heart transplant -- AGAIN. But he's sick of being sick all the time and just wants to die.
Megan Follows (S7, E14, 2001)
Megan had a tiny role as a friend/ex-girlfriend of Dr. Kim Legaspi. I didn't even recognize Anne of Green Gables at first, but that had more to do with her voice, which has completely changed over the years.
Jeffrey Dean Morgan (S7, E15, 2001)
Before he dramatically died on Grey's Anatomy, Jeffrey played firefighter Larkin, who has to have both legs amputated on the scene of a horrific train accident. When pregnant Dr. Corday starts having contractions and leaves, Carter is forced to do most of the procedure by himself.
Zachery Ty Bryan (S7, E19, 2001)
Zachery TB, domestic abuser and shoe-shamer, has a small role in this episode as a douchebag frat boy who goads a poor young man into drinking himself to death during Greek Week. Dr. Benton gets into his face but alas does not punch it. :(
Brenda Song (S7, E20, 2001)
Brenda had a small role in this episode as Lynda, a teen brought in with mysterious breathing problems and abdominal pain, who has strange markings on her back. It turns out her grandmother used hot oil and quarters to try and draw out evil thoughts when Lynda was caught kissing her boyfriend.
Amy Jo Johnson (S8, E8, 2001)
Amy played Jill, a pedestrian who is mowed down by Carter's grandmother, known as Gamma (who sped away from the scene of the accident.) In the prior episode, Gamma had been deemed unfit to drive anymore due to a medical condition. The Pink Ranger survives, but her sweet doggy, Gordon, does not. Nice going, GAMMA. (This clip is really sad and makes me cry. Poor Gordon!)
Keegan-Michael Key (S8, E9, 2001)
In his third ever role, Keegan-Michael appeared in one scene as someone named Witkowski, an assistant to Dr. Benton's lawyer. When the lawyer deems Peter's tie to be "too loud," Witkowski trades with him. Peter hates it and says so. The end.
Lea Salonga (S8, E10, 2001)
Lea had a small role in this episode as Amparo, a woman whose son falls off the roof. During the boy's exam, Amparo passes out, and reveals to the doctors that she has lymphoma. But she wants to keep it secret from her family, at least until after the holidays. She does not sing, NOR is Ming-Na Wen in the episode for a Mulan reunion. :(
Christina Hendricks (S8, 2002)
Early in her career, Christina appeared in four episodes as Joyce Westlake, Abby Lockhart's neighbor. Joyce is in an abusive marriage, and Abby regularly hears the abuse play out through the thin walls of her apartment. After convincing Joyce to seek refuge in a shelter, Joyce's nutjob husband, Brian, breaks down Abby's door and beats her up. Luka promptly gets revenge. (This is one of the few episodes I remember watching with my mom when it originally aired. Teenaged me hopefully asked, "Does Luka love her?" And my mom smiled and said, "I think so." I mean, is there anything more romantic than murderous rage?!)
BONUS CONTENT: Relevant corona-esque clip from the season 8 finale!!!
There's a possible smallpox outbreak in the ER, and everyone must remain quarantined inside of the building until the situation is under control. Shockingly, a bunch of great big stupid men have a problem with this ("THEIR RITES AND FREETUMS!!!!!!!!!"), and try to smash their way out. Carter shames them back into compliance.
Sources: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26.