In a future America, Denzel Washington is a one man army wandering the wastelands and deserts with a first generation iPod and the last surviving copy of the Bible (KJV, of course!) some 30 years after a global thermonuclear war. Then let’s throw in cannibals and biker gangs roaming the post-apocalyptic wasteland outside a town ruled by Gary Oldman.

The set up is as campy and B-grade as it sounds, but the extraordinary thing is that the Hughes brothers play it straight. The Book of Eli is a movie that doesn’t realise how absurd its premise is and doesn’t compensate for it (by way of knowing humour or taut writing), and we end up with Mad Max without the insanity or car chases, or Six String Samurai without the cult status, campiness or delicious fun, or a spaghetti western without the actual qualities of a spaghetti western.

There is something very odd about the script, which ditches the conventions of westerns (like how there must be a real reason why the antagonists deserve to be brought down by a reluctant hero) and even basic rules of storytelling. Everything that happens, happens because the scriptwriter needs it to, and not because the story itself propels itself in a certain trajectory.

There needs to be a showdown between Eli (Washington) and Carnegie (Oldman), so the Bible Eli carries becomes the Holy Grail for Carnegie, who seeks to extend his control of the region using the power of the Bible. Now, in a world where apparently no one else is literate, no one else remembers the Bible, and no one remembers even how to pray, that’s just bizarre and pointless. Why not Seven Habits of Highly Effective People or Jonathan Living Seagull? No one would be any wiser.

Even Gary Oldman didn’t have enough material this time to pull off his typical screen villainy, and you’ll be wondering through the movie why it isn’t as entertaining as you thought it would be.

To their credit, the Hughes Brothers do try. There’s some interesting fight choreography and lots of expensive CGI to approximate a bleak desert landscape (which in the old days was done for a tenth of the budget by directors of spaghetti westerns). Don’t go for a toilet break or you’ll miss the five minutes where this CGI-enhanced footage is scattered across the film.