Dear Frankie

Walking a tightrope between sentimentality and compassion requires delicate feet. Shona Auerbach, whose debut feature film this is, wears safety shoes. As a result, Dear Frankie rings false, despite terrific performances.

Lizzie's story is sad and lonely. On the run from an abusive husband, with her chain smoking mum and nine-year-old Frankie, who is deaf and cannot speak, has little of comfort to bolster depression.

Frankie thinks his dad doesn't see them because he's away at sea with the merchant navy. He receives letters, supposedly from every continent on earth, but in truth written by Lizzie - does Frankie not recognise her handwriting? - in the local library, and he writes back. This emotional thread, tying the absent father with the disabled son, is greased with corn syrup. Nothing is quite as bleak as the situation requires. Even the general store, which doubles as a chippie, is tastefully minimalist and the lady who owns it (Sharon Small) has a heart that glows in the dark.

In lazy moments, between the constant grind of 1000 words a day, novelists allow their imaginations to roam. The fruits of such daydreaming become ideas for short stories. This is a perfect example. What would happen, scriptwriter Andrea Gibb might have asked herself, if Lizzie pays a complete stranger to be Frankie's dad for a day?

There is nothing wrong with the idea. What lets it down, however, are the details. There are too many loose ends and when the identity of the stranger is revealed, it feels like one more blossom on the happy tree.

Emily Mortimer understands Lizzie's inability to stretch out and touch the world. It is an internal performance of great integrity, selfless to a fault. Gerard Butler, who flirts with stardom in Hollywood, does everything possible to play against the grain. The stranger has no charm, as shy as she is afraid, often unsure of what to say. Butler contains his natural charisma and shuts down. Jack McElhone, as Frankie, is a revelation. He has the authority to take this script and give it life. Without him, the slow dive into the pit of despair would be relentless.