Apple Original Films has released a teaser trailer for "Being Heumann," the new drama from Oscar-winning "CODA" director Siân Heder, ahead of its world premiere as the opening film of the Toronto International Film Festival next week. The film dramatises the true story of disability-rights advocate Judy Heumann, played by "Doctor Who" actress Ruth Madeley, and is based on Heumann's memoir. It marks a significant follow-up for Heder and adds a high-profile awards-season contender to Apple's slate.

The story is set in 1977, when Heumann led more than 100 disabled activists in occupying the San Francisco Federal Building, sparking a 28-day sit-in regarded as the longest occupation of a federal building in US history. The protest demanded enforcement of Section 504 of the Rehabilitation Act, requiring accessibility in federal spaces, with Mark Ruffalo playing the official obstructing the demonstrators; Dylan O'Brien, Jon Beavers, Rob Delaney and Ray Fisher also feature. The film premieres in Toronto on 10 September, opens in select cinemas on 6 November, and arrives on Apple TV on 13 November.