Based on Wally Lamb’s bestselling novel, the HBO limited series follows the parallel lives and personal turmoil of identical twin brothers. They’re both played by Mark Ruffalo.

Ruffalo is “at the top of his game.” Don’t miss his “remarkable double performance” says TV Guide abou the decades-long family saga that examines love, sacrifice and mental illness.

The can’t miss six-part limited series premieres tonight at 9 pm. Check your local listings for channels.