Gained fame as Patrick in The Perks of Being a Wallflower alongside Emma Watson. He has also starred as The Flash in Justice League and as Credence in Fantastic Beasts and Where to Find Them. His other notable works include City Island, Trainwreck, and Madame Bovary.
He sang opera music when he was six years old. After years of honing his skills, he sang in Philip Glass's opera White Raven.
He played a brief role in the television comedy Californication.
He is the son of a managing director at Hyperion publishing and Workman publishing. His father Robert served as the senior VP of Disney's adult book publishing house.