Here’s an endearing movie that’s surprisingly loyal to a novel and gets away with it. Nick Hornby has allowed his books to get kicked around — “High Fidelity” was shunted from London to Chicago — and has even conspired in the script-writing changes.

But none of that for directors Chris and Paul Heintz.

They cast High Grant as Will, a good-hearted pickup artist who preys on single mothers. Will’s romantic misadventures lead him to Fiona Brewster (Toni Colette), whose son Marcus (a wonderful Nicholas Hoult) sticks to him like flypaper. Grant and Hoult are keepers because they actually seem to care about one another. This is a compassionately funny flick with very few gimmicks. Pity about the Hollywood ending.