Cast of I Know This Much Is True

Meet the talented cast of I Know This Much Is True. From main characters to supporting roles, discover the actors who bring this show to life.

Starring: Mark Ruffalo as Dominick Birdsey / Thomas Birdsey, Melissa Leo as Concettina Ipolita Tempesta 'Ma' Birdsey, Rosie O'Donnell as Lisa Sheffer, Archie Panjabi as Dr. Patel, Kathryn Hahn as Dessa Constantine, John Procaccino as Ray Birdsey, Rob Huebel as Leo, Michael Greyeyes as Ralph Drinkwater, Gabe Fazio as Shawn Tudesco / Dominick and Thomas Acting Double