Every Actor On The Pitt Who Also Appeared On ER

Noah Wyle isn't the only actor with ties to both Cook County General and Pittsburgh Trauma Medical Center.

Though HBO Max's "The Pitt" is in no way, shape, or form a continuation of "ER," the two medical shows share more than just Wyle. In addition to several familiar faces working behind the camera on the Emmy-winning series — including series creator R. Scott Gemmill, executive producer John Wells, and physician-writer Joe Sachs — at least a half-dozen actors previously appeared on the NBC juggernaut.

Ergo, TVLine's decision to start tracking every performer who has appeared on both doctor dramas — a list we'll routinely update should additional familiar faces emerge as "The Pitt" continues its acclaimed run, which was recently extended to include a Season 3.

In addition to naming each actor, we've also noted which "ER" episodes they appeared in, should you decide to take a stroll down memory lane as you await the next new episode of "The Pitt."

Long before she became Pittsburgh Trauma Medical Center charge nurse Dana Evans on "The Pitt," Katherine LaNasa guest-starred on Noah Wyle's previous medical drama, "ER." Despite their shared TV lineage, LaNasa had no memory of crossing paths with Wyle during her brief stay at County.

"I don't even think I met Noah [at the time]," LaNasa told TVLine. She did recall meeting Maura Tierney, thanks to a mutual connection: Tierney had starred on "NewsRadio" with Vicki Lewis, while LaNasa appeared alongside Lewis on another NBC sitcom, "Three Sisters."

LaNasa also befriended fellow "ER" guest star Don Cheadle, who was on set ahead of a multi-episode arc as med student Paul Nathan. "I used to play poker with Don," she said. "I don't remember if it was 'ER' first and then the poker game, or which way it went, but I was so impressed with him."

LaNasa appeared in Season 9, Episode 4 as Janet Wilco, an overly flirtatious mom who winds up in a storage closet with Goran Višnjić's Dr. Luka Kovač. When auditioning for the role, she told TVLine she had watched "The English Patient" the night before.

"I was inspired by Kristin Scott Thomas to tap into that part of my sexuality required for that role, and I got it," she said. "I remember thinking, like, 'Yeah! The old girl got the part!'"

Long before he stepped into the role of Dr. Jack Abbot on "The Pitt," Shawn Hatosy made a lasting impression on "ER," guest-starring in Season 13, Episode 7 as Willis Peyton, a patient suffering from dissociative identity disorder. The episode was directed by John Wells, marking the beginning of a creative partnership that would span decades.

"That one role... changed everything," Hatosy told TVLine, explaining how the experience led to future collaborations with Wells, including starring roles on "Southland" and "Animal Kingdom," which ran for five and six seasons, respectively, on TNT.

"When you're doing a guest spot, you just don't know who you're going to change the mind of for the future," he said.

That partnership entered its third decade in 2024, when Wells enlisted Hatosy to recur on both "The Pitt" and Fox's short-lived "Rescue: HI-Surf." The former earned him his first Emmy for Outstanding Guest Actor in a Drama Series in 2025.

On "The Pitt," Michael Hyatt recurred throughout Season 1 as Pittsburgh Trauma Medical Center chief medical officer Gloria Underwood, a persistent thorn in Robby's side whose pleas for improved patient satisfaction scores are met with open disdain by an ER chief already stretched thin by an underfunded, understaffed department. Though Gloria is not seen in Season 2, she is referenced by new hire Dr. Baran Al-Hashimi (played by Sepideh Moafi).

Eighteen years earlier, Hyatt guest-starred in Season 13, Episode 12 of "ER" as Yvonne, a New Orleans expat who lost everything — including her husband — in Hurricane Katrina and ultimately winds up having part of her leg amputated. It was a memorable one-off, particularly because Yvonne was the final patient treated by Laura Innes' Dr. Kerry Weaver before her resignation from County General. (Fun fact: Innes was the second longest-tenured "ER" cast member, behind only Noah Wyle, appearing in upward of 250 of the show's 331 episodes.)

On "The Pitt," Tracy Vilar recurs as Pittsburgh Trauma Medical Center ward clerk Lupe Perez. She spends much of Season 1 stationed behind a window in the waiting room, fielding patients like (ugh) Doug Driscoll.

Late in the season, however, as PTMC's frontline heroes respond to a mass-casualty event, Lupe is pulled into a far more harrowing role. Alongside social worker Kiara Alfaro (played by Krystel McNeil), she helps reunite anxious family members with shooting victims — or, in some devastating cases, assists with identifying the dead.

Twenty-eight years earlier, Vilar guest-starred in two episodes of "ER" as Doris, a drug-addicted patient who first sought medical attention in one of the series' most memorable hours: the live Season 4 premiere, "Ambush." She returned three weeks later in Season 4, Episode 4, in which Doris unexpectedly goes into labor and delivers a stillborn, blaming Nurse Carol Hathaway (played by Julianna Margulies) for her baby's death.

On "The Pitt," Shu Lan Tran recurred in Season 1 as Ginger Kitajima, an elderly patient whose daughter, Rita (played by Kayla Blake), brings her in after a fall into a rose bush. In need of around-the-clock medical care, Ginger's condition places visible strain on Rita as a caregiver — yet Ginger herself remains upbeat, particularly when Dr. Robby indulges her request for a dance.

Twenty-one years earlier, Tran guest-starred in Season 11, Episode 7 of "ER" as Mrs. Pak, the mother of Mi-Cha (played by Peggy Ahn), who arrives at County with stomach pain and unexpectedly gives birth to a healthy baby boy. After Carter breaks confidentiality and tells Mrs. Pak the truth, she voices fears that her staunchly conservative husband will refuse to let their daughter return home. (The episode also featured a pre-fame Randall Park as Mi-Cha's developmentally delayed brother, Yong-Jo, who had been helping his sister keep a romantic relationship with a neighbor secret from their parents.)

On "The Pitt," Jenny O'Hara appeared in the Season 2 premiere as patient Candace O'Grady. Under the care of Dr. Samira Mohan (played by Supriya Ganesh), Candace confides in the fourth-year resident that she stopped taking her prescribed medication after discovering what she believed to be an alternative treatment. She explains that she and a friend experimented with marijuana — and that she has since taken to consuming 12 or more (!) pot-laced cookies a day, resulting in intractable vomiting.

Thirty years earlier, O'Hara guest-starred in back-to-back episodes of "ER" as floor nurse Rhonda Sterling. First pulled down from the ICU in Season 3, Episode 6 to assist Carol Hathaway (played by Julianna Margulies), Rhonda struggles with the pace of County's emergency department and accidentally hands Carol the wrong injectable during a trauma. After a second critical error in the following episode leads Carol to write her up, Rhonda reveals she is just nine months away from her pension — and that someone higher up is deliberately floating her into unfamiliar departments in an attempt to get her fired. Rather than endure further humiliation, she decides to quit, forfeiting her pension altogether.

Of course, the face of both "ER" and "The Pitt" is Noah Wyle, who earned five consecutive Emmy nominations for Outstanding Supporting Actor in a Drama Series for his role as Dr. John Truman Carter III — and, 26 years after his last nomination, secured his first win in 2025 for Outstanding Lead Actor in a Drama Series for his turn as Dr. Michael "Robby" Robinavitch.

In the first of several interviews with TVLine tied to "The Pitt" Season 1, Wyle reflected on how the project evolved as its creative focus sharpened. 

"The idea was to take a look at what was happening to the people that were on the front lines... and seeing how there appeared to be two different health care systems in our country — those for people who have money and insurance, and those who don't," he said. "The more we went down that road, the more the point got obscured in the reunion aspect, the retread aspect, the reboot aspect... so I was not sorry when we were forced to pivot [away from 'ER'] and figure out how to tell the story in a new way."

That pivot — along with making the series for streaming rather than network television — ultimately expanded its creative possibilities. "Because you're no longer [bound by] standards and practices and language barriers, you really can paint with all the colors on the palette," Wyle explained.