New HBO Max crime series casts Sophie Turner alongside Colin Firth and Toni Collette

Sophie Turner has joined the cast of The Staircase, a new crime series for HBO Max. She joins big names like Colin Firth, Toni Collette, Juliette Binoche, Rosemarie DeWitt, and Parker Posey.

The limited series is based on true events and will explore the life of novelist Michael Peterson (Firth), his North Carolina family, and the suspicious death of his wife, Kathleen (Collette) in 2001. Turner will play Margaret Ratliff, one of Peterson’s adopted daughters. 

The drama is based on the true crime documentary of the same name, which originally aired in 2004 and went on to inspire shows like the investigative podcast Serial. Director Jean-Xavier de Lestrade revisited the story twice for updates on legal developments, and Netflix released The Staircase as a 13-episode series in 2018. 

This new, dramatized version of The Staircase has been in the works at Annapurna Television since 2019, with Harrison Ford originally in talks to star as Peterson. The Devil All the Time director Antonio Campos and American Crime Story producer Maggie Cohn are on board as showrunners and writers, with Campos directing six of the eight episodes.

As for Turner, she rose to fame playing Sansa Stark in HBO's fantasy epic series Game of Thrones from 2011 to 2019, a performance which earned her an Emmy nomination and multiple Screen Actors Guild Award nominations. Since then, she's kept busy, playing a young Jean Grey in X-Men: Apocalypse and Dark Phoenix and appearing in the action comedy Barely Lethal and the revenge thriller Heavy. 

Meanwhile, on the small screen, she starred in the 2020 Quibi series Survive, playing one of two survivors of a plane crash alongside Corey Hawkins, and she's set to make her voice acting debut in the upcoming animated HBO Max series The Prince, a sitcom about the British royal family. 

The Staircase doesn't have a release date yet, but in the meantime you can fill out your watch list with our picks of the best TV shows of 2020. And, if you don't have a subscription yet, make sure to check out our list of the best HBO Max prices.