Toni Collette Cast Opposite Colin Firth in HBO Max's Crime Drama 'The Staircase'

Toni Collette is taking on an exciting new project.

The 48-year-old actress is joining the cast of HBO Max’s upcoming limited drama series The Staircase, per Deadline.

The eight-episode series focuses on the life of Michael Peterson, played by Colin Firth, and his expansive North Carolina family as well as the mysterious death of his wife, Kathleen.

Toni will play Kathleen in the show, which is based on the numerous books and reports about the case.

Michael Peterson was convicted of the murder of his wife in 2001. He had initially claimed that Kathleen died from falling down the stairs after consuming alcohol and Valium, but an autopsy found that she died from multiple injuries, including blunt force trauma to the back of her head. His charge was eventually reduced to manslaughter in 2017 and he was released from prison.

The Staircase is partially based on the true-crime docuseries of the same name which premiered in 2004 and was released on Netflix as a 13-episode series in 2018.

Check out the trailer for Toni’s latest movie, Stowaway.