Trevor Reznik (Bale) works long hours in a metalwork factory where any lapse of concentration can have grisly repercussions. But even when a colleague (Ironside) loses an arm, Trevor is preoccupied by strange notes appearing around his flat. He finds solace with a friendly hooker (Leigh) and a kindly airport cafe waitress (Sanchez-Gijon), but the sinister new guy at work (Sharian) makes his skin crawl. And since Trevor hasn't slept for a year, he has a lot of loose skin crawling over his gaunt form.

We have to wait until the end to find out just why Trevor hasn't been sleeping, and by then the film's mysteries already beginning to come into focus. This is a tricky script that digs around psychologically--Trevor is a terrifying bundle of paranoia and overreaction. And Bale conveys his haunted confusion perfectly. That he lost 63 pounds (that's 28.6kg or 4.5 stones) is hardly irrelevant--his skeletal frame looks like something from a sci-fi horror film! But Bale also gives a powerfully internalised creep-out performance.

Meanwhile, the film is show in a bleak greyscale in which everything looks like it's degenerating as much as Trevor is. Even the skies have a gloomy gothic feel that adds to the growing enigma at the film's centre. What's really going on here? Clearly, there are some massive disparities both in the story and in Trevor's brain. And as Anderson subtly references films like Memento, The Usual Suspects and Fight Club, it begins to become playfully engaging on a completely new level.

Along the way there are some almost unbearably harrowing sequences, including the metal-shop accidents, an insanely gruesome funfair ride and several creepy car chases. When we finally find out the truth, everything slots in so neatly that we're almost disappointed to discover the answers. But beneath the chills, Anderson is speaking beautifully about guilt, redemption and justice ... in a hoarse whisper.