Scrubs' 10 Best Guest Stars, Ranked

One of the most consistently entertaining sitcoms of the early 21st century was "Scrubs," following the medical staff at Sacred Heart Hospital. Though the gags come in fast and furious, often veering into slapstick comedy and the surreal, there is a genuine heart to the series. More than just depicting these young medical professionals growing into their careers and adult lives together, the literal life-and-death stakes of what they do is always in clear focus. Like "M*A*S*H" before it, "Scrubs" deftly balanced comedy and heartbreaking drama, becoming a huge element of the show's original nine-season run. (And it's coming back!)

But beyond the series' protagonist J.D. (Zach Braff) and his friends, "Scrubs" welcomed an impressive number of guest stars. More than just providing fresh faces to the hospital, many of these guest stars help make some of the best episodes of the entire show. To clarify, the actors who had longstanding recurring roles, like Heather Graham and Elizabeth Banks, are not included here as we chronicle the series' greatest guests. Here are the 10 best "Scrubs" guest stars, ranked, each memorably leaving their own mark on Sacred Heart Hospital.

Though often associated with darker and more intense roles, as with his standout performance in "The Penguin," Colin Farrell has always had strong comedic chops. These qualities are on full display in the fourth season episode "My Lucky Charm," capitalizing on the actor's smoldering sex appeal. Farrell plays Billy Callahan, an Irishman living life to the fullest, who arrives at the hospital with a man he punched out in a bar fight. Completely charming the staff, especially the women, J.D. and Turk (Donald Faison) debate whether they should turn Billy into the police for the fight and subsequent injury.

On paper, it might seem like a one-note joke that Farrell's character is irresistibly hot and unfailingly likeable. But Farrell gets considerable comedic mileage from this simple setup, making it impossible to dislike the guy. In that sense, Farrell's charms aren't exclusively for the other characters' benefit, extending to the audience as they see just how charismatic Billy truly is. Leaning thoroughly into Farrell's heartthrob status, "My Lucky Charm" showcases the actor perfectly willing to take the mickey out of himself.

Less than a year after starring in the iconic "Friends" series finale, Matthew Perry guest-starred in the "Scrubs" Season 4 episode "My Unicorn." Perry plays Murray Marks, an air traffic controller who learns that his father Gregory (John Bennett Perry) is in dire need of a kidney transplant. After discovering that Gregory is not his biological father, as he long believed, Murray initially refuses to donate his own kidney, citing years of questionable parenting from Gregory. However, J.D. helps Murray realize that Gregory was actually a good father to him at the end of the day, leading him to change his mind for the life-saving procedure.

In addition to guest-starring in "My Unicorn," Perry also directed the episode, the sole directorial credit of his career. Playing Murray's father is Perry's actual father, giving their scenes together an added verisimilitude, both in terms of comedy and emotion. It's also important to note that, even though he was fresh off "Friends" at the time, Perry was playing a character that felt very different from Chandler Bing. While his turn in "Scrubs" may not be among Matthew Perry's biggest TV roles, he was no less memorable on the show.

J.D. dated several women over the course of "Scrubs," with one standout girlfriend being Julie Quinn. Played by Mandy Moore, Julie debuts in the fifth season episode "My Half-Acre," as a blind date set up for J.D. by one of his patients. As breathtakingly beautiful as she is tremendously clumsy and prone to day dreams, she makes a seemingly perfect and similar romantic interest for J.D. Elliot Reid (Sarah Chalke) advises them to move slowly but after the two's differing views on the seriousness of their relationship, Julie leaves in the following episode "Her Story II."

A supremely underrated actor, anyone who's seen Mandy Moore's masterclass work in "This Is Us" knows how talented she is. Moore dated Braff in real-life for a time, with their romantic chemistry palpable, making her two-episode arc all the more memorable compared to J.D.'s other girlfriends. At the same time, Moore isn't afraid to get in on the more ridiculous comedic elements of the show, particularly its slapstick moments. As an added bonus, the character brings in Billy Dee Williams, playing himself, as Julie's godfather frustrated by Turk's unbridled "Star Wars" fan enthusiasm.

Dick Van Dyke has been an absolute legend in the entertainment industry for generations, including playing more than one iconic TV show role throughout his career. In the second season episode "My Brother, My Keeper," Van Dyke appears as veteran physician Doug Townshend, an old friend of the hospital's chief of medicine Bob Kelso (Ken Jenkins). An enormously amiable presence, Townshend even manages to keep the Janitor (Neil Flynn) to stop picking on J.D., at least temporarily. However, Kelso notices that Townshend continues to use outdated procedures and practices, something that Townshend admits to, forcing him into retirement.

At the time, Van Dyke was fresh off starring in the long-running medical series "Diagnosis Murder," with his "Scrubs" appearance playing off that part. The guest-starring role also takes advantage of the venerable actor's reputation for playing heartwarming characters to great effect. Seeing Townshend face the realization that his medical techniques and, by extension, himself, have become obsolete, is a heartbreaking subversion of expectation. Blending humor and the life-and-death drama of the medical field, Van Dyke fits perfectly in the overarching ethos of "Scrubs."

The early episodes of "Scrubs" featured the younger main characters still learning the ropes of working in a busy hospital and dealing with the pressures of life-saving work. One person who couldn't quite make the cut was fellow intern Nick Murdoch (Sean Hayes), appearing in the first season episode "My Super Ego." In the face of this gifted physician who is a personable hit with the rest of the staff, J.D. feels threatened. Shortly after being recognized as the hospital's top intern, Nick resigns when he can't handle the mental toll of losing a young patient.

If you only know Sean Hayes from "Will & Grace," his guest-starring spot on "Scrubs" gives him a lot more range to work with. As Nick, he gets to not only turn on his usual comedic charm but also explore a fragility under the surface, despite his character's presumed line of work. This is all informed by the rivalry that forms with J.D., eventually turning into a begrudging respect albeit perhaps too late. Hayes fit in right with the rest of the show's cast, making his character's brief tenure all the more impactful when he left.

Not all of the memorable guest stars on "Scrubs" were other physicians and J.D.'s love interests, of course. So many of the patients that were treated at Sacred Heart throughout the series also left a deep impression, including the terminally ill George Valentine (Glynn Turman). Appearing in the Season 8 episode "My Last Words," J.D. and Turk's plans for a celebratory steak dinner are interrupted when they are asked to check in on George. As the duo get to know him, they decide to postpone their plans to console and comfort George in his final moments.

"Scrubs" has long acknowledged inspiration from "M*A*S*H" and "My Last Words" feels like an episode that displays that influence prominently. So much of the episode is centered on Turman's character and he beautifully captures the anxieties of someone staring at death in the face. The entire episode is a meditation on mortality, with George's conversations with J.D. and Turk revealing their own lingering fears about death. That only works if the guest star pulls it off and Turman does so beautifully in one of the penultimate season's best episodes.

The late Emmy Award-winning actor Kathryn Joosten played plenty of lovably acerbic characters in the latter years of her career. This includes her recurring guest character on "Scrubs," Mrs. Tanner, debuting in the Season 1 episode "My Old Lady." Facing severe kidney failure, Tanner assures J.D. she'd rather die than go through dialysis, feeling she had lived a satisfying life. Joosten reprised her role as Tanner in fantasy sequences imagined by J.D. in the episodes "My First Kill" and "My Finale," greeting him from beyond the grave.

If Glynn Turman's George Valentine depicts the anxiety in facing death, Kathryn Joosten's Mrs. Tanner depicts its serenity. Tanner's interactions with J.D. uncover his own insecurities about death, including the inevitability that he will lose patients, even if by their own volition. Joosten brings these sensibilities to life marvelously and whenever she returned to the show, it was always a treat to see that dynamic revisited. While Joosten deservedly gets more widespread accolades for her performances in "The West Wing" and "Desperate Housewives," her role in "Scrubs" also warrants acclaim.

Many of J.D.'s fun-loving sensibilities come from his father Sam Dorian, played by fan-favorite sitcom veteran John Ritter. Sam only appears in two episodes, starting with the first season story "My Old Man" and ending with the following season's "My Lucky Day." In Ritter's first appearance, J.D. reconciles with the fact that his father tried the best he could to raise his son while his return was for a childhood flashback sequence. To acknowledge Ritter's death in 2003, the fourth season episode "My Cake" reveals that Sam died, with his children coping with their father's legacy.

With how strongly J.D. looked up to his mentor Perry Cox (John C. McGinley) as a surrogate father figure, he'd always have a complicated relationship with his actual dad. Ritter fills out that expectation marvelously, more specifically in his first guest-starring appearance in the series. There's also the bittersweet element of art imitating death, reflecting his passing in a somber way for the Dorian brothers. Another loss acutely felt by the show, watching John Ritter on "Scrubs" will make you miss him all over again.

Another guest star with a two-episode arc on the series was Michael J. Fox, who appeared in the third season as visiting doctor Kevin Casey. Introduced in the episode "My Catalyst," Casey wows everyone at Sacred Heart with his impressive medical acumen to the point where J.D. considers naming him his new mentor over Cox. This is derailed when it becomes clear that the new doctor suffers from a severe case of obsessive-compulsive disorder, deeply affecting his job performance. In the following episode, "My Porcelain God," Casey imparts his final wisdom to J.D. and Elliot before leaving the hospital for good.

"Scrubs" creator Bill Lawrence had worked with Fox since their previous television series "Spin City" before the actor left to address his Parkinson's Disease diagnosis. With their collaboration to bring Kevin Casey to life, it's clear the duo hadn't lost a creative step working together. Casey captures a lot of the archetypes presented throughout "Scrubs," someone cool and professional on the surface, but struggling immensely on the inside. For fans of the collaborative pair, Bill Lawrence and Michael J. Fox will reunite on "Shrinking," continuing their professional relationship in another heartwarming dramedy series.

Of all the patients who came to Sacred Heart, none left a deeper impact on the characters and audience than Ben Sullivan. Played by Brendan Fraser, Sullivan debuts in the first season episode "My Occurrence" as a patient treated by Cox, with his cancer seemingly in remission by the episode "My Hero." However, in the third season episode "My Screw Up," it's revealed that Ben's leukemia not only resurfaced but caused him to die through cardiac arrest. The death is so upsetting to Cox that he hallucinates interacting with his old patient until J.D. brings him back to his senses.

Fraser lights up virtually every scene he appears in throughout "Scrubs," playing the most amiable cancer patient to ever grace a television series. That makes Ben's death the most heartbreaking loss in the entire show, set up by one of its most ingeniously staged twists. The normally unflappable Cox was utterly destroyed by losing his patient, adding an enduring emotional depth to the blustering character. Bringing so much unbridled joy to the series before his loss delivered its deepest emotional gut-punch, Brendan Fraser is easily the best guest star on "Scrubs."