What good is a revenge that you don't remember? And how can you grieve for a lover you can't forget? These are the dilemmas that haunt Leonard daily, hourly, from moment to moment... they haunt him because they are among the few constants in his surreal life. And yet his never-to-be satisfied desire for vengeance and his impossible-to-mourn lost love are the only things that keep him going.

But as Leonard's tale deravels, we are granted the perspective -- the hindsight -- that he will never have. Is someone manipulating Leonard into killing the wrong John G.? Why is an insurance salesman from San Francisco -- as we discover Leonard is -- wearing a designer suit and driving a car he could never afford, one with Nevada plates? Knowing how Memento begins/ends doesn't spoil the fun, not in the least. It's not getting there that's half the fun in Memento, it's finding out how we got there.

The upshot of Leonard's condition is that he is constantly meeting people with whom he has a history -- such as Teddy and Natalie (Carrie-Anne Moss: Chocolat, Red Planet) -- people who are helping him find John G., whoever he is, and yet every meeting is new to Leonard. Nolan's running the story backward has the effect of putting us in Leonard's brain -- a lot of important stuff has happened, but we can't remember it. We have to rely on Leonard's notes -- like the one inked on the Polaroid of Teddy that reads: "DON'T BELIEVE HIS LIES HE IS THE ONE KILL HIM" -- just as Leonard does.

"Don't tell me how it ends!" is the typical cry of the suspense fan -- but how Memento ends and how it begins are one and the same. And yet they aren't. Because Memento replicates the problem that Leonard suffers from, which is the inability to form new memories. Since the attack that killed his wife and left him with a nasty whack on the head, Leonard can remember nothing for more than a few minutes -- he keeps track of his world with Polaroid photos of the people and places around him and with detailed notes about who's who and what's what. The really important notes -- like "JOHN G. RAPED AND MURDERED MY WIFE" -- are tattooed on his body.

It does work, brilliantly. Mind-blowingly. The film opens on a Polaroid photo of a body facedown on a blood-splattered tiled floor, and as a hand shakes the photo -- the way you do to make a Polaroid develop faster -- the image fades. We're going back in time. And then the next scene we see is the one that occurred before this, in which we witness a rather unkempt-looking man in an expensive suit -- that would be Leonard Shelby (Guy Pearce: Ravenous, L.A. Confidential) murder, in apparent cold blood, a weaselly little guy -- that would be Teddy (Joe Pantoliano: Olive, the Other Reindeer, U.S. Marshals).

How do you tell a story backward? The question that had been obsessing me from the moment I heard about Memento, the suspense film by written and directed by Christopher Nolan (based on a short story by his brother Jonathan) that has been the darling of festival audiences in recent months. The idea was intriguing, but would it work?