La La Land has taken the top honour at the Toronto film festival.
The Los Angeles-set musical world premiered on the opening night film of the Venice film festival and screened in Telluride, before debuting in Toronto.
The film is the follow-up by Chazelle, 31, to audience-pleasing drumming drama Whiplash, which won three Oscars, including best supporting actor for JK Simmons.
La La Land is his second musical, following Guy and Madeline on a Park Bench, a little-seen micro-budget jazz musical, originally planned as his thesis project for Harvard Film School.