Adapted from the 1998 novel by Wally Lamb, the clip features Ruffalo as Dominick and Thomas Birdsey, who live in gloomy Connecticut. Thomas, heavyset in a windbreaker, is a paranoid schizophrenia, while Dominick is thinner with a beard. The latter struggles to help the former, while being questioned by a doctor (played by Archie Panjabi). Rosie O’Donnell stars as social worker Lisa Sheffer, who tells Dominick that his brother is “seriously mentally ill.”
The trailer features flashbacks of the men as boys, as well as adult Thomas running into oncoming traffic. “I need you to stand up for me for once,” Thomas later tells Dominick, covered with cuts and bandages while laying in a hospital bed.
The series was written and directed by Derek Cianfrance, known for 2010’s Blue Valentine and 2012’s The Place Beyond the Pines. O’Donnell last appeared on SMILF, which was canceled in 2019. I Know This Much Is True also stars Melissa Leo, Kathryn Hahn, Juliette Lewis, Archie Panjabi and Imogen Poots.