Also joining the cast of the six-part I Know This Much Is True is Imogen Poots, who will play the live-in girlfriend of one of Ruffalo's twin brother characters. I Know This Much Is True, based on Wally Lamb's 1998 novel of the same name, follows the parallel lives of identical twin brothers, both played by Ruffalo.
TOPICS: I Know This Much Is True, HBO, Archie Panjabi, Imogen Poots, Juliette Lewis, Kathryn Hahn, Mark Ruffalo, Melissa Leo, Rosie O'Donnell, In Development