Photo: Samuel Goldwyn Films

Four years ago, Los Angeles Times reporter Steve Lopez began a series of columns about Nathaniel Ayers, a Juilliard-trained classical musician who was living on the city's streets, beset by schizophrenia and scratching out Beethoven sonatas on a grubby, two-stringed violin. Ayers's journey toward a new life (Lopez helped hook him up with lessons from L.A. Philharmonic performers and an apartment of his own) is recounted in Lopez's book The Soloist and now in a film starring Jamie Foxx (flinty and introverted as Ayers) and Robert Downey Jr. (adorably bedraggled as Lopez).

The formula might seem familiar: mental illness + artistic genius + Hollywood stars = inspiration-in-a-can. But The Soloist, directed by Joe Wright (Atonement), resists easy urges to pluck at your heartstrings; it has the shape, momentum, and offhand humor of ragged real life (Wright cast some of the extras from L.A.'s homeless community). Its feet planted firmly on the streets, The Soloist is compelling because it doesn't romanticize the limits of Ayers's beautiful mind, of Lopez's compassion, or of music as a magic elixir. The film's victories taste sweeter for being small and hard-won.