HIS name may not be easy to remember, but M Night Shyamalan's accomplished, daring films are impossible to forget.

Last year's trick-playing debut The Sixth Sense was still haunting the mind months later, and his second dark and creepy journey into supernatural suspense will follow suit, thanks to his science-fiction union of the film-making instincts of Steven Spielberg, Frank Capra and Alfred Hitchcock.

"Just as The Sixth Sense was not just a horror film, Unbreakable is not just a thriller," says writer-director Shyamalan. "It tells a story about very real characters who are experiencing very real problems and emotions just like the rest of us."

The "very real" central character is David Dunn, a second successive low-key turn in a Shyamalan shaggy dog story for the normally hyper Bruce Willis. Dunn is a done-in, vulnerable kind of guy, a down-to-earth Philadelphia football-stadium security guard whose under-achieving life has just hit its lowest ebb on a train journey. On removing his wedding ring, his advances have been rejected by the young executive woman in the next seat.

This close call for her is followed by a miraculous escape for him. Dunn is the sole survivor when the train crashes, prompting him to re-evaluate his stymied marriage; re-assess his unfulfilled relationship with his son and address his nagging feeling that he was destined to do more in his time on earth.

He is not alone in that belief. Elijah Price, a man of mystery with the name of a prophet and bones as fragile as glass, runs a comic-book gallery and is looking for a death-defying superhero in flesh form. He thinks he has found his unbreakable man in Dunn, leaving him a calling card to set up a meeting.

Elijah (Samuel L Jackson) might be on to something, not least because the self-questioning Dunn has avoided the clutches of death on more than one occasion. So, under Elijah's encouragement, this Everyman character puts himself to the anything-but-Everyday test of being an angel of mercy, taking on nocturnal hooded duties in the manner of Batman to discover if he really is a force for good imbued with super-heroic powers.

It is at this point that reaction to Unbreakable will diversify: some will see Dunn's angelic mission as a moving sequel to Capra's It's A Wonderful Life. Others - probably the camp who don't read comic strips - will merely think his actions to be absurd.

I say, stick with it, because the final sting in this spooky, downbeat tale is worth the indulgence, even if the twist does not quite match the shock factor of The Sixth Sense.

Willis, denuded of his quips and blockbuster action, gives an impressively restrained performance. A question mark in human form, his Dunn counter-balances the exclamation-mark demean-our of the volatile Jackson, who overcomes the distracting handicap of his maddest hair since his Pulp Fiction Afro.

With Unbreakable, M Night Shyamalan has confirmed a talent to amaze.