(M) *

Director: Michael Bay.

Cast: Mark Wahlberg, Stanley Tucci, Nicola Peltz, Jack Reynor, Kelsey Grammer, Li Bingbing, Sophia Myles, Titus Welliver, T. J. Miller.

IT'S becoming increasingly difficult to figure out which Transformers movie sucks the most.

It's definitely not the first one, which was bafflingly awesome, but as the series continues the first one looks more and more like a fluke and that rarest of beasts - a truly good Michael Bay film.

Now the race to the title of Worst Transformers Movie has a new contender to rival Revenge Of The Fallen (#2) and the almost-as-bad Dark Of The Moon (#3): ladies and gentlemen, presenting Age Of Extinction.

Having dispensed with Shia LaBeouf and whoever the Megan Fox replacement was in Dark Of The Moon, Bay has taken a vaguely different tack in part four, which is set four years after the "Battle Of Chicago" that climaxed the previous film.

Since then, the CIA (led by Grammer's shifty black ops leader) has been hunting down Transformers - both good (Autobots) and bad (Decepticons) - and turning them over to tech company KSI (led by Tucci's Steve Jobs-like Joshua Joyce).

In the eyes of the CIA, all Transformers are alien terrorists, and in the eyes of KSI, Transformers are the key to the future of weaponry.

But Grammer and his stooges are having trouble finding the last few Transformers, particularly their leader Optimus Prime.

Meanwhile, near-destitute Texan inventor Cade Yeager (Wahlberg) buys a broken-down truck for $150 and, well, anyone who's seen any of the previous three movies or watched the TV show as a kid will know where this is heading.

Firstly, believing Wahlberg is a near-destitute Texan inventor is one of the toughest tasks inflicted by a casting director on an audience since John Travolta played a woman in Hairspray or Denise Richards played a nuclear physicist in The World Is Not Enough.

That's fine, we all like Wahlberg, and he's a great actor in the right film. Unfortunately, he's not the kind of lead who can elevate a bad film (like for example The Happening).

But that is the least of this film's worries.

There's a little thing called "the suspension of disbelief" which happens every time you walk into a cinema. For the duration of the film, you will believe the unbelievable, whether it be that men have cloned dinosaurs and put them in a theme park, or that there are secretly a bunch of wizards running around England, or even that a bunch of living robots have come to Earth in search of something called the Allspark. This allows you to buy into the film's world and enjoy it.

That's all well and good but it's when a film's own internal logic doesn't make sense that movies become truly unbelievable and this is what makes Age Of Extinction a ludicrous, mind-numbing waste of two and three-quarter hours.

So much of this film makes little sense, characters make infuriatingly dumb decisions, stupid coincidences pop up a lot, Bay wastes time with cut-able nonsense when the film is already way too damned long, and every time you think you can forgive him because something half-way intelligent or cool happens, he drags you kicking and screaming back to the basement with some kind of "what the?" moment.

By the time you get to the movie's supposed nerdgasm  - Optimus Prime unleashes the Dinobots - you will be long past bored, your mind vapourised in an endless wave of computer-generated carnage, pyrotechnics, pathetic attempts at characterisation, and a barrage of product placement.

There's one shining diamond in the manure here and it's Stanley Tucci. He is too good for this film, and what he does with his character is too good for this film, and the fact that his character is reasonably well rounded and actually has a proper arc is too good for this film. It makes you feel even sorrier for Wahlberg having to deliver line after line of "over-protective dad" schtick which stops being funny or necessary 10 minutes in.

It's a tough call as to whether this is worse than the terribly edited Revenge Of The Fallen. At least we can see the action taking place here, as repetitive and overly explosive as it is, but within a couple of hours of watching it you will be struggling to remember much of the film at all.

Which might be a good thing.