Going straight isn't really a viable option for Sherry (Gyllenhaal) an ex-junkie and petty thief who's barely able function from day to day.

Placed in a dispiriting parole hostel, she's got to keep to a strict curfew or risk getting sent back to pokey to serve two more years.

A brittle sunniness masks a nest of insecurities she once coped with by taking drugs ("heroin was the love of my life") and hitting the bottle.

Using sexual favours to win short-term benefits from a succession of seedy men, her novel approach to job hunting (taking her top off) lands her a post in childcare.

However, her main concern is becoming a mother to the young daughter who barely remembers her. "I stole from people to buy money to get drugs," she tells the uncomprehending sprog.

A short fuse and a total lack of self-worth mean Sherry is at constant risk of breaking the terms of her parole, a situation which just places greater pressure on her.

To be fair, Sherry isn't the sort of character to elicit much sympathy. But that's also her strength - she doesn't angle for pity.

It's Gyllenhaal's richest role since Secretary and she perfectly captures the flaws and neuroses of a newly sober addict making the first foray into a brave new world.

Honest and finely observed, Sherry is just the tonic.

Tim Evans