Matt Ryan, the star of NBC series “Constantine,” and Judith Light have signed on to appear in the Roundabout Theater Company’s upcoming Broadway production of “Therese Raquin,” headlined by Keira Knightley in her Broadway debut.

Ryan will play the man whose passionate affair with protagonist Therese (Knightley) turns dangerous in the production set for an October opening. The show marks Ryan’s Broadway bow, although in the U.K. he’s been a member of the Royal Shakespeare Company since 2004. (“Constantine,” the TV series in which he played the title character, did not get renewed for a second season on NBC.)

Gabriel Ebert, a Tony winner for his performance in musical “Matilda,” is also on board for Helen Edmundson’s stage adaptation of the Emile Zola novel. He’ll play the Camille, Therese’s caddish husband, with Light, the “Transparent” actress who’s won two Tonys (“Other Desert Cities,” “The Assembled Parties”), portraying Camille’s domineering mother. Evan Cabnet (“The Model Apartment”) directs.

“Therese Raquin” is part of a Broadway season at the Roundabout that also includes Clive Owen in “Old Times,” Laura Benanti and Josh Radnor in “She Loves Me” and Jessica Lange in “Long Day’s Journey Into Night.” [source]