I Know This Much Is True

Dominick Birdsey must confront the consequences of his twin brother Thomas's violent public episode, which forces him to take on an unexpected role in Thomas's defense. As he deals with the aftermath, Dominick reflects on their troubled childhood under their abusive stepfather, Ray, and their shared longing to discover the identity of their unknown biological father.

Dominick's relationship with his girlfriend, Joy, becomes strained as media attention grows around his brother Thomas' case. While seeking Thomas' release from the Hatch Institute, Dominick meets social worker Lisa Sheffer, who may be able to help, though he soon realizes the challenge may be greater than anticipated.

Dominick prepares for a crucial hearing with Hatch’s review board that may determine his brother Thomas's future, with Sheffer's guidance. A run-in with an old classmate triggers difficult memories from Dominick's childhood, prompting him to reflect on his time at college with Thomas, when he first met Dessa and began noticing signs of Thomas's illness. Meanwhile, Joy tries to address and improve the issues in her relationship with Dominick.

Dominick returns to work before fully recovering from his accident, despite concerns from those close to him. As he endures the effects of heavy medication, he experiences disturbing memories related to Thomas's initial hospitalization, with the hours ticking down to Thomas's upcoming hearing before the Hatch review board.

Dominick investigates his Sicilian grandfather's early 1900s immigration to Three Rivers and begins to believe his family is under a curse. A surprising development regarding Thomas leads him to take bold measures.

Dominick and Ray's long-standing feud escalates during a public confrontation at a critical moment. In the aftermath of a sudden tragedy, Dominick begins to make amends with those he has wronged.