Harry Styles has finally debuted his dramatic chops, charming the Toronto International Film Festival at the world premiere of “My Policeman.”An emotional, decade-spanning drama about a 1950s cop juggling an idealistic wife and a secret male lover, Styles turned up with his costars Emma Corrin and David Dobson to unveil the long-awaited project.The company of actors and their director, Michael Grandage, received a standing ovation at Toronto’s Princess of Wales theater following the Sunday night premiere. Applause was cut short thanks to Styles’ schedule — the singer had to catch a plane immediately after the screening to resume his world tour.At a brief Q&A, Styles discussed how he and his costars built an authentic bond as on-screen friends, and navigated some soul- and body-baring love scenes with both. “Having a base of a real friendship outside of the characters … it doesn’t require much acting. In the more intense scenes, there’s a lot of trust and safety there,” he said.