At first rather annoying in its heavy emphasis on reenactments, this movie ultimately proves fascinating, simply because the complicated, highly dramatic tale it tells still almost defies belief.

This is a must-see and one of the best documentaries - and films - of this year.

It's the kind of movie you'll want to see a second time with someone who hasn't seen it yet, to remember what it was like to watch it for the first time.

A film of deceptively outspoken contemporary relevance, this is cinema at its most alert, alarming and alive.