The Dark Horse has won best film at the Seattle International Film Festival.

James Napier Robertson’s movie tells the story of New Zealand bipolar speed chess champion Genesis Potini.

Its star, Cliff Curtis, has been named best actor. He beat Sir Ian McKellen and Jason Segel to the award. 

The Golden Space Needle Awards are voted by the festival's audiences.

Genesis Potini was a highly regarded speed chess player, and founded the Eastern Knights chess club for underprivileged children.

He died in 2011, aged just 48. Mr Potini was buried in Gisborne.