It’s rare that the biggest role of your life happens to also be the most controversial — especially when you’re 71 years old. But that’s the only way to describe the whirlwind of the last few months for Reed Birney, the esteemed character actor and Tony-winning Broadway regular who has wowed critics and shaken audiences with his turn in Blue Film, the debut feature helmed by Elliot Tuttle on a budget under $100,000.

Birney portrays Hank Grant, a former middle-school English teacher who spent seven years in prison for attempting to sexually assault one of his students. The movie opens with him hiring an adult sex worker who goes by Aaron Eagle (Kieron Moore), and who was actually another one of his students, named Alex, well over a decade ago. Hank has engineered their fraught evening together to confess he was in love with Alex back then, to explain himself and see what has come of his onetime pupil. What develops is a discomfiting, emotionally intense exploration of intimacy between the two men, rooted in the traumatic, troubled origins of their student-teacher bond.

It’s also as stark and frank a portrait of a pedophile as you’ll find in American movies, making for a meal of a role for Birney, who’s known onscreen mostly for small parts in big shows like House of Cards, The Blacklist and Gossip Girl. His performance here is fearless, committed to capturing the warped, mangled humanity in a man that many viewers would consider irredeemably monstrous. It’s overflowing with shame and regret, anchored by an uneasy genuineness. It’s the kind of work that would, or should, vault an actor as underrated and experienced as Birney firmly into the awards conversation, were the film not as intently disturbing as Tuttle’s final product.