The film is impressively mounted and Schaefer has made a directorial debut of distinction, but it is an uncomfortable ride from the opening scenes of Chapman arriving in New York to the inevitable, inexorable final scene.
Leto, who gained poundage for the role, keeps taking his shirt off just to make it clear that he is the latest in a long line of actors to confuse daily patronage of the local doughnut shop with intensive actorly preparation.
Don't hammer this film for trying to get inside the head of Mark David Chapman before he shot John Lennon outside the rock legend's New York apartment on December 8th, 1980. Hammer it instead for failing to do so with any depth or insight.
Chapter 27 is a smart attempt to distill the twisted psychology and motivation of Mark David Chapman, which we've all superficially gleaned through mass-media reports and intermittent updates on Chapman's incarceration.
Some viewers may well find Chapter 27 sleazy or distasteful, and I won't argue the point. But Schaefer's movie creates its own highly compelling world, which is pretty much the prime directive in filmmaking.