The fourth instalment of the Transformers franchise kicks off in the dinosaur era, and by the time the movie is over, you feel like you lived through every year that has passed since. The almost three hours of robot bashing will leave your ears ringing and, in all honesty, the plot is so loose and the explosions so many that the film could finish at least five times before it finally crashes its way to the end. 

Picking up four years after the climactic events of Dark of the Moon, we find the Autobots, led by Optimus Prime, on the run from dodgy CIA man Harold Attinger (Kelsey Grammer). Attinger is in cahoots with billionaire tech mogul Joshua Joyce (Stanley Tucci); they want to melt the Transformers down and use their metal to create their own super robot army.

Blocking their path, and fighting for the future of humanity, are all-American daddy-daughter duo Cade and Tessa Yeager (Mark Wahlberg and Nicola Peltz), as well as Tessa's Irish race car-driving boyfriend, Shane Dyson (Jack Reynor). 

While rummaging through an abandoned cinema, inventor Cade comes across what looks like a banger of a truck and tows it back to his barn. While tinkering under the hood, he soon discovers that it's not a truck, it's Optimus Prime. Cade pulls out all the stops to get the Autobots' leader back up and running, leaving the towering giant of metal mass in his debt.

The debt needs to be repaid almost immediately when Attinger and his band of not-so-merry-men come looking for Optimus. Declared criminals for aiding and abetting a supposed intergalactic enemy, the human heroes are forced to go on the run. This is where Reynor makes his first proper entrance, and, with him at the wheel for an impressive car chase, he certainly makes an impact. It's just unfortunate that despite having a lot of screentime he does not have much more to do until the final stunt sequence, which is a long way off. 

The early stages of this Transformers movie are actually quite entertaining as director Michael Bay introduces new characters, sets up the Transformers as fugitives and drops in some very impressive stunts. However, once it hits the 60-minute mark the constant barrage of explosions and metal-on-metal fighting begin to take their toll. Add heavy product placement, nausea-inducing camerawork and a script full of holes to the mix and it really becomes something of an endurance test. 

Suzanne Byrne