If there was a gold statuette for wall-to-wall compassion, Precious would wipe the floor with its rivals. Director Lee Daniels and writer Geoffrey Fletcher’s adaptation of Sapphire’s novel Push oozes empathy from the first scene to the last. It’s inescapably bleak, but occasionally it has the confidence to emerge from the shadows of its tragic story – the tale of Precious (Gabourey Sidibe), an obese 16-year-old teenager in ’80s Harlem who is abused by her mother and father – to indulge in sly humour and jolly camaraderie before retreating again into the darkness at its heart.

‘My name’s Clarissa Precious Jones… and I want to be on the cover of a magazine,’ says Sidibe. What she gets is less glitzy: we learn of the gross difference between the refuge of her mind and the reality of her life. When her vile mother (Mo’Nique, grotesque but in the end almost sympathetic) screams, ‘I should have aborted your ass,’ Precious imagines herself walking the red carpet. Most movingly, when she looks in the mirror, she sees a girl who is more beautiful and more white.

But Precious is a film about real escape, not dreams. Precious attends a special school with an inspirational teacher (Paula Patton), begins sessions with a social worker (Mariah Carey, unobtrusive) and fights her self-loathing tendencies to make new friends. It’s not an easy battle and Daniels has a tendency to land new blows when you think the fight is over. So extreme is Precious’s background that you imagine terrible things are about to happen even when they’re not.

Precious has great performances from Sidibe and Mo’Nique, but the film is arguably more heart than art. Is that such a bad thing? Perhaps not: when a film gives dignity to characters barely ever portrayed on screen, you can forgive some clumsy, emphatic storytelling and a narrative that’s too episodic and reliant on voiceover. It’s a film with a genuine message: act – don’t dwell – on your dreams. A genuine Obama-era movie, then.