Jonny Lee Miller ably captures Obree's weary struggle, never overplaying like a lesser actor might have. Thanks to Miller's performance, Obree's demons don't define him but are simply of him -- in the way most people's demons are. There are no histrionics here, no wide-eyed ravings of a man on the brink. The result is an artfully sketched likeness that's both sympathetic and believable. The rest of the cast -- particularly erstwhile Hobbit Billy Boyd as Obree's manager, Malky -- also rises to the occasion. But the script by John Brown, Simon Rose, and Declan Hughes unfortunately doesn't. Because for all the hinting that the writers and director Douglas MacKinnon do at Obree's mental battles, they never quite explain what's behind all the pain. Flashbacks to a young Obree being bullied -- as horrible as these incidents may be -- don't feel like reason enough. (In real life, Obree's brother's death was a big catalyst for his decline, but none of that material is found here.)

Moreover, Obree's marriage to his wife, Anne (Laura Fraser), hardly appears threatened by his melancholy -- which, frankly, seems implausible. And his motivation for constantly setting the bar high isn't clear. (Reduced to working as a bike messenger, he suddenly aims to break a world record, foregoing the more-expected winning-smaller-races route.) With the rock bottom of the hero's life glossed over, the highs don't seem quite so euphoric. And isn't that swing from dark to light precisely what makes going to sports movies so worth the ride?