In October 2020, HBO announced plans to set new appointments for season four of In Treatment, the acclaimed and award-winning drama series that ran for three seasons from 2008 to 2010. So far, Uzo Aduba and Anthony Ramos have been cast in the upcoming season, which will revolve around therapist Dr. Brooke Lawrence (Adubo) and her trio of weekly psychiatry patients.

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Based on the popular Israeli series Be Tipul, In Treatment featured an ensemble of skilled veteran players and a raft of pre-famous young acting talent. Some have gone on to much bigger things, while others have faded away from the limelight.

Alex Wolff

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In just the fifth acting credit of his young career, Alex Wolff played Max Weston in seven episodes of season three. Max is the son of Paul Weston (Gabriel Byrne), the primary therapist the show is centered on. Of course, Byrne and Wolff also played father and son in the frightening 2018 horror film Hereditary.

Max's arc in the series includes leaving his mother's home in Baltimore to live with his father Paul in Brooklyn. This adds extra parental stress onto Paul's plate, which he struggles to keep balanced with his professional life.

Melissa George

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Australian actress Melissa George was a ubiquitous face in the mid-aughts, appearing in such high-profile horror movies as The Amityville Horror remake and 30 Days of Night. She can next be seen in the upcoming series The Mosquito Coast.

During her eight-episode run on In Treatment, George plays Laura Hill, Paul's very first patient on the show. The anesthesiologist complicates the patient-doctor privilege when she becomes sexually infatuated with him. The tricky dynamic also shapes Paul's moral arc as the show progresses.

Dane DeHaan

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Before he was flying around in Chronicle and terrorizing Spider-Man as the Green Goblin, Dane DeHaan got his start as the troubled teenager Jesse on In Treatment.

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Jesse is an adoptive homosexual teenager who begins fostering violent ill-will toward his parents. As Paul tries to get through to him and help him find a healing path forward, Jesse's wild outbursts reach a fever pitch when he's contacted by his biological mother.

Hope Davis

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Two-time Golden Globe nominee Hope Davis was a well-established and acclaimed actress long before joining the cast of In Treatment. In addition to a slew of indie films in the 90s, Davis starred in such awards contenders as About Schmidt and American Splendor. She also plays Maria Stark, Iron Man's mother in Captain America: Civil War.

Davis earned one of her Golden Globe nods for her role as Mia Nesky on In Treatment, one of Paul's former patient who returns 20 years later to resolve old baggage.

Amy Ryan

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Following her Oscar-nominated turn in Gone Baby Gone, Amy Ryan joined the cast of In Treatment season three. But, rather than playing one of Paul's weekly patients, Ryan plays Adele Brouse, Paul's new therapist he visits every Friday.

Paul begins seeing Adele after a neurologist friend recommended her for sleep medication. As Adele probes into Paul's personal life, he resents her at first but soon learns to respect and admire her methods as a psychoanalyst.

John Mahoney

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Most famous for his role as Frasier's hilarious father Martin Crane, the great English actor John Mahoney passed away in 2018. The Say Anything and Barton Fink star also had a seven-hour arc as Walter Barnett on In Treatment's second season.

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Walter Barnett is a successful but high-strung CEO who is prone to crippling panic attacks. With the weight of the world on his shoulders, Walter can't cope with the mounting pressures in his life. He visits Paul every Thursday to alleviate the stress, but his stubbornness often gets in the way.

Debra Winger

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The three-time Oscar-nominated Terms of Endearment star Debra Winger disappeared from the limelight between the years 1995 and 2001. Then after appearing in just six movies over the next seven years, Winger joined the cast of In Treatment season three.

Winger plays Frances, a celebrated actress who visits Paul every Tuesday when she starts having problems remembering her lines. Frances also expresses deep concern over her mother and sister's shared breast cancer diagnosis and the heritability of the disease.

Irrfan Khan

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Irrfan Khan was not just one of the all-time greatest Indian actors who ever lived, he was one of the finest actors, period. The Life of Pi and Slumdog Millionaire star passed away in 2020 at the young age of 53.

Khan joined the cast of In Treatment season two as Sunil, Paul's first patient of the week. Every Monday, Sunil expresses his deep depression over the death of his wife before emigrating to the U.S. As he struggles to live with his adult son and daughter-in-law, Sunil feels shame over the need for therapy, a major taboo in his native culture.

Alison Pill

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Although she began her career as a child actress at age 12, Alison Pill didn't find superstardom until her role as Kim in Scott Pilgrim vs. The World in 2010. One year prior, she gave one of the most memorable turns on In Treatment season two.

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Pill plays April, a bright young architecture student with the world in front of her. However, April has a secret that she keeps from everyone except Paul: she was lymphoma. As Paul tries to get her to come to terms with her illness, April denies the seriousness of her condition.

Mia Wasikowska

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Before she was traversing Wonderland and chasing the Mad Hatter around, Aussie actress Mia Wasikowska blew audiences away with her performance as Sophie, a suicidal teenage gymnast on In Treatment's first season.

As Sophie grapples with her parents' divorce and the sexual relationship she has with her far-older gymnastics coach, Paul begins to get through to her and instill her with a sense of hope. Sophie is one of the few characters to be changed for the better after her therapy sessions.

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