Viewed from here, where American football remains, for most of us, a curiosity, this film about a doctor who challenged the sports-entertainment industrial complex behind the game is something of a revelation.
The fight that Dr Bennet Omalu took to the NFL over the long-term effects on players of the head-smashing game - those helmets only protect the skull, not its free-floating contents - wasn't front-page news as it became in the United States in the noughties.
It's engaging enough, especially with Will Smith depicting the Nigerian-born Omalu in one of the better dramatic performances of his career.
Smith is really good. In another year, he might have made the cut for best actor Oscar consideration - which would have had a nice symmetry with his previous nod, playing Muhammad Ali in the days before those blows to the head took their toll.
But the trouble here is, the virtuous, brilliant, Omalu pretty much is the movie. He's one heck of a whistleblower but it's just not much of a tune. And Smith's role becomes burdened by how much of it is spent bestowing a sainthood on the guy to accompany the many specialist medical degrees he has acquired before and after immigrating to the US.
