Jacob Tremblay, Joan Allen and William H Macy have joined Brie Larson on the cast of Element Pictures and No Trace Camping’s drama, which has started production. A24 holds US rights and StudioCanal will distribute in the UK. FilmNation sells internationally.

Lenny Abrahamson directs from a screenplay that Emma Donoghue adapted from her book about a young boy who grows up with her mother incarcerated in a small chamber.

Sean Bridgers, Tom McCamus and Megan Park have also come on board. Elevation Pictures will distribute Room in Canada.

The shoot takes place at Pinewood and in Toronto, with Screen Scene in Dublin handling post-production.

Element Pictures’ Ed Guiney produces with David Gross. Executive producers are Andrew Lowe for Element Pictures and Jeff Arkuss and Jesse Shapira for No Trace Camping, as well as Emma Donoghue, Rose Garnett and Tessa Ross.