The survival thriller Whalefall opens in theatres on October 16, and early tracking points to a modest debut: Box Office Pro projects a $10-15 million opening weekend in North America. The 20th Century Studios film, adapted from Daniel Kraus’s acclaimed 2023 novel, is one of the season’s most unusual releases.

The film stars Austin Abrams as Jay Gardiner, a scuba diver who is swallowed whole by a massive sperm whale while searching off California’s Central Coast for his father’s remains. Trapped inside with roughly an hour of oxygen, Jay must rely on the lessons his father — played by Josh Brolin — taught him to survive. Elisabeth Shue, John Ortiz, Jane Levy and Emily Rudd round out the cast. Kraus co-wrote the screenplay with director Brian Duffield.

Duffield, known for No One Will Save You and Spontaneous, has said he wanted the audience to feel trapped inside the whale alongside Jay. The film will open the 19th Toronto After Dark festival, and a new clip released September 30 shows Abrams and Brolin in a calm, character-focused moment at sea. Abrams reportedly swam with sperm whales to prepare for the role, and advance tickets are already on sale.