T.R. Knight (Grey’s Anatomy, 42, The Good Wife) has joined the cast of Hulu Original event series 11/22/63, from J.J. Abrams’ Bad Robot Productions and author Stephen King. Adapted for television by Bridget Carpenter (The Red Road), 11/22/63 centers on Jake Epping (James Franco), an unassuming divorced English teacher who stumbles upon a time portal that leads to September 9, 1958, and goes on a quest to prevent the assassination of John F. Kennedy, which occurred on November 22, 1963. But his mission is threatened by Lee Harvey Oswald, his falling in love and the past itself — which doesn’t want to be changed.

Knight will play Johnny Clayton, a salesman in 1960s Texas who can’t quite break up with his estranged wife Sadie Dunhill (Sarah Gadon), even as she falls in love with Jake (Franco). Charismatic but controlling, Johnny confronts Jake in a tense encounter that puts Jake’s double life at risk. But there’s equal danger in what will happen if Jake and Sadie expose Johnny’s own secrets.

King, Abrams, Carpenter and Bryan Burk executive produce; Franco will serve as a producer. Warner Bros. TV, where Bad Robot is based, is the studio.