The Severance cast is full of recognizable and big-name actors who have previously appeared in popular TV shows and movies. Premiering on Apple TV+ in February 2022, Severance boasts a star-studded cast, including veteran actors like Christopher Walken, Adam Scott, and Patricia Arquette, among others. It also features directorial work from actor Ben Stiller, in another departure from his more traditional comedic fare, and Aoife McArdle, highlighting its industry pedigree and credentials.

Severance follows a mysterious company called Lumon Industries, which offers its employees a medical procedure called severance, which separates their personal and professional lives. The show focuses primarily on Mark (Adam Scott) and his team as they go through the workday motions, though their job responsibilities are not immediately made clear. Mark's life is upended when a former colleague reintroduces himself outside the office, spurring Mark to investigate Lumon's true intentions. Apple TV+ is no stranger to these types of streaming shows, and with 14 Emmy nominations for the first season, they delivered big time once again.

Adam Scott as Mark Scout

Adam Scott stars as Mark in the Severance cast, the newly appointed lead of the Macro Data Refinement team at Lumon. Mark is grieving the death of his wife and opts to have the severance procedure, which separates any work-related memories from his personal ones, bringing new meaning to work/life balance. That way, he doesn't remember anything regarding his work or job title when he leaves the office for the day and doesn't know what's going on at home when he enters Lumon in the morning. By the end of the first season, he wants to quit but has yet to decide if he will deactivate his chip and leave.

This is Scott's second collaboration with Stiller, the first being in Stiller's film The Secret Life of Walter Mitty. Scott is best known for playing geeky accountant Ben Wyatt in a very different office setting on Parks and Recreation and appeared as Ed Mackenzie on Big Little Lies. On top of Severance, Scott also appeared in the Apple TV series Loot and voiced Ron Staedtler in the Netflix animated series Inside Job​​​​​​.

Britt Lower as Helly

Britt Lower stars as Helly in the Severance cast, Mark's new colleague in the severed department who refuses to comply with corporate procedure. When she discovers the split between her "outie" or outside the office and "innie" or inside the office personas, she seeks to merge the two and quit her role at Lumon. Her realization that she agreed to this separation further complicates matters. By the end of the first season, it was also discovered that she is the daughter of Lumon Industries CEO Jame Eagan and she almost prefers death to her current life. Lower has been in Future Man as Jeri and Man Seeking Woman as Liz. She also appeared in an episode of American Horror Stories, "Facelift."

John Turturro as Irving

John Turturro plays Irving in the Severance cast, a senior staffer, and a stickler for the rules at Lumon Industries. He also prides himself on knowing the Eagan family, Lumon's enigmatic founders. Irving risks his position at the company when he develops a more-than-platonic relationship with a colleague in Christopher Walken's Burt. However, by the end of the season, it turns out that Irv's outie is a military hero, and he has a trunk full of Lumon's shady business practices, making his by-the-books character even more intriguing.

John Turturro has collaborated with the Coen Brothers in Barton Fink, The Big Lebowski, and O Brother, Where Art Thou?, and appeared in the Transformers movies as Agent Simmons. He also appeared in HBO's The Plot Against America in 2020 and took on the role of mob boss Carmine Falcone in Matt Reeves' The Batman in 2022.

Zach Cherry as Dylan

Zach Cherry plays Dylan in the Severance cast, Mark's comic-relief coworker who is constantly theorizing as to what is happening to themselves outside Lumon Industries. When Helly joins their department, his conspiracy theories increase. It was Dylan who helped the innies figure out who they were. Cherry has played bit parts in a variety of television shows and movies, the most well-known appearances being in Netflix's You as Ethan, serial killer Joe's coworker at the bookstore in season 1, and Shang-Chi and the Legend of the Ten Rings as Klev. In 2023, he played Jim in the Julia Louis-Dreyfus comedy movie, You Hurt My Feelings.

Tramell Tillman as Milchick

Tramell Tillman stars as Milchick in the Severance cast, a Lumon employee who oversees those who have received the severance surgery. He rewards and punishes Mark's team based on their performance and serves as a reminder of Lumon's control over its employees, at least during the working day. Tillman has been featured in a few television shows like Godfather of Harlem and Dietland. He also had a two-episode arc as Detective Sommers in the Nazi-hunting Prime Video series, Hunters.

Severance Supporting Cast & Characters

Patricia Arquette as Harmony Cobel: Harmony is Mark's mysterious and eccentric boss in the Severance cast, who may have a bigger role to play in the severed employees' outie lives. Patricia Arquette has amassed an impressive filmography over the years, first appearing as Freddy Krueger victim Kristen Parker in A Nightmare on Elm Street 3: Dream Warriors. Severance is her second collaboration with Stiller, as she played Tilly Mitchell in Escape at Dannemora. In 2023, she took on the lead role in the Apple TV series High Desert.

Christopher Walken as Burt: Burt is a senior staffer at Lumon in the Severance cast who is friends (and maybe something more) with Irving. Walken has had an award-winning and eclectic career, earning an Oscar for his performance in The Deer Hunter and playing everything from the Headless Hessian in Sleepy Hollow to the archangel Gabriel in The Prophecy. He also had a recurring role in the BBC series The Outlaws.

Yul Vazquez as Petey: Petey is a former Lumon employee and Mark's work friend whose position is taken over by Mark. Petey confronts outie Mark, who does not remember their work friendship, due to his severance surgery. Actor Yul Vazquez has been in several streaming series, like The Outsider, Russian Doll, and Narcos: Mexico. In 2022, he took on a major role in Epix's Godfather of Harlem and one of the lead roles in HBO's White House Plumbers.

Dichen Lachman as Ms. Casey: Ms. Casey, portrayed by Dichen Lachman, is a Lumon employee whose job title remains unclear. However, by the end of the season, Mark learns she is his wife, who he thought was dead. Lachman has held roles in Altered Carbon, Agents of S.H.I.E.L.D., Raya and the Last Dragon, and Jurassic World: Dominion. In 2022, she provided voice work for the Disney animated series Baymax! and played Soyona in Jurassic World Dominion.

Jen Tullock as Devon: Devon, played by Jen Tullock, is Mark's sister concerned about his involvement with Lumon. Tullock has held roles in The Coop and Perry Mason.

Michael Chernus as Mark's Brother-in-Law: Michael Chernus is Mark's unnamed brother-in-law in the Severance cast, who also worries about Mark's decision to sever himself at Lumon. He has appeared in Orange is the New Black and Spider-Man: Homecoming. In 2023, he took on the role of Tom in the Prime Video miniseries remake of Dead Ringers.