Not for the faint-hearted, John Woo's unflinching account of individual destinies caught up and mangled by the greater madness of the Vietnam War remains his greatest cinematic achievement to date. More a three-act tragedy of epic proportions than a conventional action film, it follows the fortunes of Ben, Paul and Frank, three Hong Kong youths raised in poverty who have little to depend upon except their unswerving friendship for each other. When Ben kills a local hoodlum in a revenge beating and is forced to flee to Saigon, his two friends come with him, dreaming of the fortune they intend to make together on the Vietnamese black market. What they find instead is a world gone mad, ruled by gangsters, murderous fanatics and rogue soldiers who have taken the law into their own hands.

There's a brutal and compelling grandeur to Woo's vision of Asia in the late 1960s, one that refuses either to take sides or romanticise the past. Whether it involves a crowd of student demonstrators clashing with riot police, a nightclub shootout or a helicopter attack on a Vietcong POW camp, the film's depiction of violence has a mythic intensity which crowds in around the three main protagonists, testing their loyalty to the breaking point.

Tony Leung brings out the vulnerability and drive of the young Ben, while Jacky Cheung gives an electrifying performance as Frank, half-crazed from the bullet lodged in his skull after Paul tries to shoot him in the head. Reduced to carrying out street executions to pay for the morphine he needs to deaden the excruciating pain, his mute agonies hang like a vengeful cloud over the film's closing moments as Ben hunts Paul down, forcing him to atone for his cowardly act of betrayal. Bullet in the Head is harrowing, matchless and unrelenting. --Ken Hollings