KEY POINTS:
For all that it feels like a docudrama - and although it is directed by the man behind Touching the Void and One Day in September and diverse television documentaries - this energetic, sometimes mesmerising but ultimately rather aimless film about the bloody tyrant Idi Amin is a work of fiction.
Amin is real all right (Whitaker's titanic performance seems overblown but is doubtless understated) but the source is a 1998 novel by English-born, Malawi-raised journalist Giles Foden about a Scots doctor, a character concoction reportedly based on several real people.
Scotsman Nicholas Garrigan (McAvoy) heads for Uganda after graduation to inject some adventure into a life he fears will become fat and suburban. He gets imprudently involved with a harried but lustrous expat (Anderson) and, by happenstance, with the general who has just seized power.
He is first on the scene after a car accident in which Amin is slightly injured and is rewarded for his attention with admission to the dictator's inner circle.
Whitaker, most of whose roles have been tender, slightly rueful characters, seizes this one with both hands. That lazy eye, normally cute, looks positively eerie, and we constantly have the sense that anything could happen.
But dramatically, the film is about Garrigan, a portrait of a slight and slightly seedy personality intoxicated by the appeal of a massive one.
The problem is that it's hard to take an interest in the fate of an opportunistic little weed who imagines that impregnating a megalomaniac's mistress, for example, might be an action free of consequence.
The film conveys the heady, headlong sense of what it must have been like as the darkness descended over Uganda, but Whitaker's set-pieces of spittle-flecked fury are not enough to plug the film's dramatic holes.
Cast: Forest Whitaker, Gillian Anderson, James McAvoy
Director: Kevin Macdonald
Running time: 124 mins
Rating: R16, violence and content that may disturb
Screening: SkyCity, Rialto, Lido, Hoyts, Berkeley