Brie Larson delivers a mesmerizing performance in A24's first trailer for "Room," Lenny Abrahamson's adaptation of the bestselling novel by Emma Donoghue.

Inspired by the real-life Fritzl case, the story is told from the perspective of 5-year-old Jack (Jacob Tremblay), who's held captive in a small room with his mother (Larson). The official synopsis can be found below.

Premiering at the Toronto International Film Festival before receiving limited release on Oct. 16 (followed by nationwide distribution on Nov. 6), "Room" also stars Joan Allen and William H. Macy.

Told through the eyes of five-year-old-Jack, "Room" is a thrilling and emotional tale that celebrates the resilience and power of the human spirit. To Jack, the Room is the world… it’s where he was born, where he and his Ma eat and sleep and play and learn. But while it’s home to Jack, to Ma it’s a prison. Through her fierce love for her son, Ma has managed to create a childhood for him in their 10-by-10-foot space. But as Jack’s curiosity is building alongside Ma’s own desperation — she knows that Room cannot contain either indefinitely.