After 25 years of toy production, sticker albums and cartoons, the screenwriters had a wealth of Transformer backstories to go on when creating the first live-action movie of the 80s franchise.

And with director Michael Bay’s budget being larger than at least two continent’s combined GNPs, Transformers - with its ridiculous stunts and multi-stranded plot - is almost epic in scale.

Bay’s frenetic vision, unfortunately, is not necessarily best suited to epic filmmaking, particularly when the end product goes through this many edits.

Sam Witwicky (Shia Leboeuf) is a geeky teen looking for his first car and, subsequently, his first girlfriend. A trip to the local secondhand dealership soon solves the first problem, and the battered Camaro literally does its best to help Sam solve his girl issues.

For this Camaro is no ordinary car, but Bumblebee, a Transformer sent to protect Sam and use his assistance to help the Autobots, a friendly race of giant robots-cum-cars, find a very important artefact.

However, the evil Decepticons want the artefact for themselves, for its ability to give life to ordinary household machines would be rather useful in their efforts to take over Earth.

It’s not long before the Decepticons' search leads them to Sam, whose fate, unbeknownst to him, is inextricably linked with that of the Transformers.

LaBeouf’s Sam works as a focal point for a plot obsessed with 25 foot machines, while his chemistry with Megan Fox provides plenty of room for Bay to manoeuvre when not working on the stunning effects shots.

Able comic support from Julie White and Kevin Dunn as Sam's parents is undermined by the over-hammed performances of Jon Voight, as the beleaguered Secretary Of Defence, and Jon Torturro as a shady government type. Both actors perform as though the target audience is way younger than the 20-somethings originally enamoured with the Hasbro toys.

While most of 2007’s summer blockbusters have been criticised for their bum-numbing running times, Transformers loses some of its scale in the efforts to get it down to a cinema-friendly length.

The final act was vastly changed from the original script – note, with thanks, Turturro’s complete disappearance – yet for all the criticisms, Transformers is a summer action popcorn movie, and in that sense it’s a wonderful success.

The fight sequences are astonishing - in particular the opening, in which a military base is attacked by a rogue helicopter that lands, turns into a giant robot, and - in a fashion typical of the director - tosses tanks through the air like confetti.

Meanwhile, Optimus Prime is given multiple moments of cool, Bay’s use of Peter Cullen, Prime’s original vocal talent, helping to heap on the nostalgia.

Some plot points get lost in all the carnage (of both the on-screen and editing variety), as Rachael Taylor’s techno-whiz plotline is rendered somewhat pointless before it reaches a conclusion and one character’s demise is all but unnoticed until long after the event.

Yet it’s not the weaker elements of the production that will be most oft discussed – more so the robots turning into a seemingly endless array of modes of transport, sometimes while shifting at 100mph on the motorway.

Thus, in spite of Bay’s over zealous cutting, Transformers survives on the strength of the action, the effects and a heavy dose of nostalgia.

The plastic toys may or may not have had the 1200 moving parts Bay's CGI creations boast of (depending on how well looked-after they were), but they were certainly never this cool.

Rich Phippen