THE MOMENT of truth — when it finally comes — has the snap, crackle and pop of a Chinese fortune cookie. The Bride (Uma Thurman) has cornered her nemesis, Bill (David Carradine), in his plush Mexican hideaway, and one of these super-heroes will surely die. Thurman wants to kill Bill, but she also wants to find out why her mentor and his lethal squad of samurai assassins, the Deadly Vipers, have spent four-and-a- quarter blood-soaked hours trying to kebab her in both parts of this Quentin Tarantino epic.

The simple reason, croons Bill, casually shooting a drug-laced dart into her left thigh, is that none of them could possibly exist in a “normal” world. Like Superman, they are comic-book heroes. They wear their underpants over their tights. That’s the real uniform. Clark Kent’s dithering idiot is the costume. This, argues Bill, is what distinguishes them from the real world.

It’s also, possibly, what distinguishes Tarantino from his peers. His artful, ego-mad point is that he and his characters are larger than life. They are, as Bill puts it, “renegade killer bees” (or maverick film nuts), not faceless drones. They are not supposed to run off to El Paso, marry “a jerk”, and live happily ever after. That’s the blurry, acrobatic logic of the film.

Hence the ghastly, murderous opening of Kill Bill: Vol 1 when the anti-hero of the title puts a bullet in Thurman’s head at point-blank range during her wedding rehearsal, and leaves her for dead. It’s this cold-blooded charity that Thurman wants to avenge, and it’s bitterly spiced by the loss of her unborn child.

“OK, I overreacted,” says Carradine’s leathery Bill with delicious understatement. “But there are consequences to breaking the heart of a murdering bastard.”

It’s the perverse comic precision with which Tarantino joins the evil dots that gives the film its kick. Every detail is so carefully rigged and referenced to potential twists and iconic turns that you can never relax into the slippery plot. And what of the plot? Having skewered most of the cast in Kill Bill 1, Thurman has only two major players to negotiate before a poker duel with Carradine’s charismatic pimp. The reckoning with Michael Madsen’s alcoholic Budd and Daryl Hannah’s one-eyed Elle Driver are fabulous pieces of trailer-trash horror.

The unexpected and unforgiving melodrama is the sheer amount of suffering that Thurman has to absorb. She takes more hits than Jim Caviezel in The Passion of the Christ. She is kicked black and blue, takes two barrels of rock salt to the chest and is buried alive in a coffin in one of the most intense and claustrophobic scenes I’ve seen. This is not a film engineered to secure or inspire female viewers.

Thurman looks desperately stringy. The face is hard and angular, the straw-blonde hair lacklustre, the eyes stony blue. She looks fresh out of rehab and desperate for a fix. While she plays her desperation for real, the film wanders off to impress the gallery.

There is much to admire but little to love. Tarantino is not a director who engages on an emotional level (I doubt he engages much with real life). The most gripping moments of Kill Bill 2 are commandeered by Carradine in black-and-white moments in the El Paso church the day before Thurman’s wedding.

But she is acting and emoting in a perfect vacuum. The back-story of her life — notably her samurai training with Pei Mei (Gordon Liu) — is an homage to classic Shaw Brothers films and a martial arts star who stepped into Bruce Lee’s plimsoles in 36th Chamber of Shaolin in 1978.

But that’s as personal as Tarantino gets. He can spark new and original cinema magic by bashing genres together in the space of a single scene, but he can’t generate an ounce of human chemistry.

Kill Bill: Vol 2 is a revenger’s comedy. In the way that Akira Kurosawa exploited the Wild West to illuminate his classic Japanese melodrama Seven Samurai, so Tarantino reverses the current to inform his batty western.

What makes the young American director such a force is his terrific sense of humour and preternatural feel for the absurd, whether it be Pei Mei’s bushy white eyebrows or the kung-fu way he strokes his 3ft-foot long white beard.

The film simply wouldn’t work without this sensory overload, which smothers the queasy suspicion that what keeps us in our seats is nothing more than blind greed for the next cute nuance or visceral sensation.

Morally the film is as infantile as its rigid code of honour — and there’s not much of that between hired assassins, or directors and critics. The Midas touch is Tarantino’s ability to switch mood and genre — and take his audience with him — in the blink of an eye.

The climax of this blood-soaked odyssey, with its Sergio Leone standoffs, bleached John Ford landscapes, Hitchcockian sense of noir, Ang Lee high-wire tricks, refrigerated Clint Eastwood anger and self-referential importance, is the Dr Frankenstein belief in its own importance. Ultimately, this is a film about an obsession with film. It’s made by a man clearly deranged by trivia, but also an artisan who can pluck something unique and exciting from the collision of two (or ten) completely different genres.

Perhaps the most exciting thing about Tarantino is his refusal (or inability) to discriminate between art forms. One puff of cold reality and this house of cards will fold. But Tarantino never allows us a decent interval to draw that fatal breath.

That’s the high-wire skill. And the Peter Pan pleasure.

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