The Monkey cast features Theo James, Tatiana Maslany and Christian Convery. This info article contains minor spoilers and character details for Osgood Perkins’ 2025 movie on Disney+ and Hulu. Check out more cast guides in Vague Visages’ Know the Cast category.

The Monkey focuses on twin siblings named Hal and Bill. Twenty-five years after a series or tragic accidents, the protagonists reunite and discuss the past. The narrative follows Hal and Bill as they strategize against a killer toy monkey. Here’s every actor and character in The Monkey, an adaptation of Stephen King’s 1980 short story.

Read More at VV — Know the Cast: ‘Longlegs’

The Monkey Cast: Theo James as Hal/Bill

Character Profile: An American twin. His father disappeared in 1999 after a toy monkey killed a shop owner. Hal reunites with his estranged twin sibling, Bill, who seeks revenge for his mother’s death.

James’ Resume: Four in the Divergent Movie Franchise (2014-16), Sidney Parker in Sanditon (2019-), Robert Michaels in Dual (2022), Cameron Sullivan in The White Lotus (2022), Eddie Horniman in The Gentlemen (2024)

Read More at VV — Know the Cast: ‘Hold Your Breath’

The Monkey Cast: Tatiana Maslany as Lois

Character Profile: Hal and Bill’s mother. She raised two kids by herself after her husband’s sudden disappearance. Lois dies from a “boomerang aneurysm.”

Maslany’s Resume: Sarah Manning/Cosima Niehaus/Alison Hendrix in Orphan Black (2013-17), Erin Hurley in Stronger (2017), Petra in Destroyer (2018), Sister Alice McKeegan in Perry Mason (2020), Jennifer Walters/She-Hulk in She-Hulk: Attorney at Law (2022)

Read More at VV — Know the Cast: ‘Immaculate’

The Monkey Cast: Christian Convery as Young Hal/Young Bill

Character Profile: The main protagonists during a 1999 timeline. They experience dark days and emotional trauma after their father’s disappearance. Young Hal and Young Bill see their babysitter get decapitated at a restaurant.

Convery’s Resume: Jasper Sheff in Beautiful Boy (2018), Gus in Sweet Tooth (2021-24), Henry in Cocaine Bear (2023), Ethan in Barron’s Cove (2024), Oliver in Invincible (2025)

Read More at VV — Know the Cast: ‘Nightbitch’

The Monkey Cast: Colin O’Brien as Petey

Character Profile: Hal’s estranged son. He desperately wants a healthy relationship with his father. Petey and Hal ultimately gain control of the titular monkey.

O’Brien’s Resume: Young Craig in Mr. Harrigan’s Phone (2022), Matthew in S.W.A.T. (2022), Grayson Friedman in Grey’s Anatomy (2023), Edward in Dear Edward (2023), Young Willy Wonka in Wonka (2023)

Read More at VV — Know the Cast: ‘Talk to Me’

The Monkey cast also includes:

• Adam Scott as Captain Petey Shelborn
• Elijah Wood as Ted
• Rohan Campbell as Thrasher/Ricky
• Sarah Levy as Aunt Ida
• Osgood Perkins as Uncle Chip
• Tess Degenstein as Barbara
• Danica Dreyer as Babysitter Annie
• Bea Perkins as Florence
• Kingston Chan as Lt. Pepper
• Zia Newton as Dwayne

Q.V. Hough (@QVHough) is Vague Visages’ founding editor.