A story of redemption achieved by killing as many people as possible, "Machine Gun Preacher" is morally confused -- which certainly doesn't disqualify it as big-screen entertainment.
But what might throw audiences for a loop is why the real-life Sam Childers -- played in Marc Foster's ridiculously violent movie by the omnipresent Gerard Butler -- does anything he does. No doubt a fascinating and complicated figure, Childers is shortchanged by a film that puts him through any number of changes -- from drug-abusing, thug, thief and bar-fighting biker to born-again Christian and child savior in Sudan -- without explaining much of anything.
Certainly, the outrages of the Sudanese civil war -- in which children are recruited as soldiers or sex slaves through intimidation, mutilation and forced murder -- are horrifying, and provide a source of both righteous indignation and visceral satisfaction when Childers turns the tables. But ultimately the fact-based story seems cheapened by an adaptation so gleefully shallow and violent.
Religious audiences might respond to the Childers story, although the impetus behind his religious conversion is as loosely explained as his decision to leave for Sudan and start killing members of the Lord's Resistance Army, the renegade militia group responsible for the aforementioned atrocities. This sort of implies that Childers, rather than being an authentic example of spiritual enlightenment, is simply an obsessive character, one who does everything on impulse. But this would imply a lack of depth in "Machine Gun Preacher," and that's already been established.