Pacific Rim Uprising

Guillermo del Toro's 2013 film Pacific Rim was a rare beast indeed, a sprawling special effects-laden blockbuster that wasn't based on an existing franchise.

The film's giant Kaiju aliens and the gargantuan Jaeger robots humans use to battle them coming directly from the mind of Del Toro screenwriter Travis Beacham, and although it didn't win any accolades for subtlety, its nerdy charm and the appeal of its central conceit - to work the robots need two human pilots to link their brain to the machine (known as 'drifting') - won science-fiction fans' affection.

Now we're back for the sequel, albeit without the original's stars, Idris Elba and Charlie Hunnam, under the direction of debut filmmaker Steven S. DeKnight. Pacific Rim Uprising moves on to the next generation, with John Boyega playing Jake Pentacost, the rebellious son of Elba's character, the general who sacrificed himself to end the war that dominated the first movie.

Jake's a dropout from the Pan-Pacific Defence Corps pilot academy, where he was supposed to train to control Jaegers like his father. Instead, he now gets by selling leftover technology from the war on the black market. While attempting the theft of a rare component, he encounters Amara (Cailee Spaeny) an orphaned teen with the technical skills to build her own diminutive and unauthorised Jaeger. After the pair are arrested, Jake's forced to cut a deal with his adoptive sister (Rinko Kikuchi), to return to the academy to train cadets, including Amara, who's taken on as a raw recruit. There he rekindles a rivalry in love and war with Nate Lambert (Scott Eastwood), his former co-pilot.

Just as Jake and Amara are beginning to settle in, they discover that humanity may be facing a new threat in the shape of a mysterious rogue robot and drone Jaegers built by ruthless entrepreneur Liwen Shao (Jing Tian) and Dr. Newton Geiszler (Charlie Day).

Geiszler has been seduced away from his scientific partner from the first movie, Dr. Hermann Gottlieb (Burn Gorman) by a cushy job at Shao's corporation, creating the drones that are supposed to defend against the next alien attack, but that may hide a sinister secret that could destroy the world.

The set-up may seem complex, but it's not - there's still plenty of CGI robots bashing aliens. However, without Del Toro on board, this sequel lacks some of the charm of its predecessor. DeKnight's film isn't helped by a botched script that often reverts to cliche, and it's difficult to tell what's more wooden - the writing or Eastwood's acting.

There is however, some fun to be had. The central concept, that the giant mechanoids at the centre of the story are controlled by humans, still holds up. The special effects are typically bombastic - but it's the human connection to the technological marvels that gives Pacific Rim the edge over Transformers, its soulless merchandising fuelled rival.

It is Boyega though who elevates the film above depressing mediocrity, proving he can carry a major film franchise as a charismatic leading man. His renegade swagger is reminiscent of Will Smith's Captain Steven Hiller in Independence Day, and the Star Wars alumni develops his character from rebel to mentor - giving lazily written lines more impact than they deserve. His rapport with Spaeny, a newcomer surely set for big things, is also a highlight.

Pacific Rim Uprising will disappoint those who wanted the intriguing idea at the heart of Del Toro's original to become something more substantial - but as throwaway entertainment, it just about does the job.