Based on the 2001 novel of the same name by Helen Cross, the film explores the romantic relationship between two young women from different classes and backgrounds.

Working class Mona (Natalie Press), whose once-hotheaded brother Phil (Paddy Considine) became a born-again Christian in prison, meets upper middle class Tamsin (Emily Blunt, in her theatrical film debut) who suffers from a lack of love in her family.

Mona finds Phil getting rid of all the alcohol in their late mother's former pub, situated below their living quarters.

After going to prison for petty theft and violence, Phil has undergone a religious transformation and now uses the pub to host meetings of local Christians.

At Tamsin's house, she and Mona enter her sister Sadie's bedroom, where they find a bag of magic mushrooms.

He angrily chokes Tamsin, then releases her and forces Mona to return home with him, locking her in her bedroom.

Mona grabs Tamsin by the throat and holds her under the water, as if to kill her, but eventually releases her and walks away.

Whereas the novel pays a lot of attention to the social background of England in the 1980s, Pawel Pawlikowski focused on the relationship between Mona and Tamsin.

Pawlikowski has expressed he was not interested in portraying typical teenage life in England, and instead wanted to give the movie a certain "timeless feeling".

In an interview with the BBC, Pawlikowski said, [...]If you wanted to make a film about British teenagers it would be ... well, it wouldn't interest me, let's put it like that.

[16] Roger Ebert of the Chicago Sun-Times, who gave it three out of four, described it as "a movie that is more about being an age, than coming-of-age" and appreciated Pawlikowski's pacing.

Scott termed it "a triumph of mood and implication",[18] and James Berardinelli of ReelViews called it a "gem" lost in the "hype" of Hollywood blockbusters.

[19] Ty Burr of The Boston Globe deemed it "a conceit on a number of levels" and "confused between an 'artistic' lesbian movie and Heavenly Creatures", while commending Blunt's performance and the cinematography and declaring that "at its most interesting, [it] offers us the sight of people desperately embracing faith in the hopes it will pull them through".

[20] Steve Schneider of Orlando Weekly called it "slight and predictable at its core" but praised the performances and the "black humor" between the female characters "that endows the movie with most of its genuinely entertaining moments".

[24] At the Evening Standard British Film Awards, Pawlikowski won for Best Screenplay, as did both Blunt and Press for Most Promising Newcomer.