William Gregory Magnussen is an American actor. He has been featured in the films Into the Woods (2014), Bridge of Spies (2015), Birth of the Dragon (2016), Game Night (2018), and Aladdin (2019), and has had supporting television roles in Get Shorty (2017) and Maniac (2018). In 2021, Magnussen starred in the sci-fi series Made for Love on HBO Max and appeared in the films The Many Saints of Newark and No Time to Die. In 2023, he starred as Rey "The King" Kingston in Spy Kids: Armageddon.

Into the Woods is a 2014 American musical fantasy film directed by Rob Marshall, with a screenplay by James Lapine based on his and Stephen Sondheim's 1987 Broadway musical of the same name. Produced by Walt Disney Pictures, it features an ensemble cast that includes Meryl Streep, Emily Blunt, James Corden, Anna Kendrick, Chris Pine, Tracey Ullman, Christine Baranski, Lilla Crawford, Daniel Huttlestone, MacKenzie Mauzy, Billy Magnussen, and Johnny Depp. The film is centered on a childless couple who set out to end a curse placed on them by a vengeful witch, and the characters are forced to experience the unintended consequences of their actions. It is inspired by the Grimm Brothers' fairy tales of "Little Red Riding Hood", "Cinderella", "Jack and the Beanstalk", and "Rapunzel".