Who’s Who In The I Know This Much Is True Cast — Besides Mark Ruffalo

If you're looking for a doozy of a series to get completely sucked into — and then maybe go back and read the book, HBO has you covered. Its latest limited series, I Know This Much is True airing on Sky Atlantic now in the UK, is based on the book of the same name first published in 1998. The novel quickly rose in popularity thanks to Oprah’s beloved (and now defunct) book club. Well, there’s always time to pick it back up now!

I Know This Much is True follows the story of twin brothers Thomas and Dominick (Mark Ruffalo) and how they’re both coping with struggles and hardships in their adult lives. And spoiler alert: they’re both dealing with some pretty heavy stuff. Thomas is suffering from severe bouts of mental illness which means Dominick seeks out treatment for him. Along the way, Dominick works on trying to better himself, too. If that’s not enough, Dominick is also busy reading about his grandmother, learns about his real father and mother’s history, and uncovers what he can about his extended family and their long history of twins. 

Ruffalo is pulling double duty as both Dominick and Thomas, but he’s not the only very familiar name in this very talented cast.