The lessons of Finding Dory are commendable, but why make a children’s film so complicated?

Pixar's latest animation, a sequel to Finding Nemo, gives forgetful fish Dory a lead. Plus: Jason Bourne.

Amnesia is a concern for the heroes of two blockbuster sequels – the Pixar animation Finding Dory and the espionage thriller Jason Bourne. The condition extends to the film-makers, who have forgotten much of what made the original movies so appealing. In fairness, the 2003 Finding Nemo lacked the emotional complexity of top-drawer Pixar. But its story of an anxious clownfish combing the ocean for his lost son served as a neat rebuke to worrywart parents, and it featured one enduring character: the Pacific blue tang Dory. Her short-term memory loss left her in a state of carefree enchantment perfectly expressed by Ellen DeGeneres, whose voice calls to mind a rubber ball thrilled afresh by each new bounce.

Now Dory has a movie of her own, in which she goes in search of the parents from whom she was estranged as an infant. Many of the previous picture’s fish chip in to help, but the script’s argument for inclusivity and diversity is made most persuasively by Dory’s new allies. Hank is a tomato-red octopus who can’t bear to be touched, while Becky, a frizz-haired loon, and Gerald, a bullied sea lion, have learning difficulties that leave them vulnerable to mockery by their fellow creatures. Heroism originates here with the apparently disadvantaged, whose differences ultimately prove to be no sort of disadvantage at all.

The message is commendable, so it’s unfortunate that the execution is so complicated. Incident is stacked upon incident, most clumsily during a final half-hour in which the sea creatures take chaotically to the roads. When there are lulls in the action, these are filled too often by homilies and life lessons that demand no spelling out.

Quality control remains high in the area of animation. From the velvety anemone beneath a lattice of rippling sunlight to the pink-tinted ocean surface at dusk, it is clear that nature needs to up its game to keep ahead of Pixar. The biggest gasps should be reserved for Hank’s extraordinary chameleonic powers, which allow him to blend into a laboratory wall and to mimic a potted plant or a handrail. Impersonating a baby in its stroller, he uses his Mr Tickle arms to propel himself at high speed like a wheelchair-basketball champ tearing up the court. In a film that largely plays it safe, Hank brings a jolt of anarchic danger.

The breakneck editing and neck-breaking violence of the Bourne series, about a brainwashed CIA killing machine who gradually recovers his memory and goes rogue, has been the biggest influence on action cinema since the advent of the car chase. There have been only three instalments until now (four if you count the spin-off The Bourne Legacy) but their style is so ubiquitous it feels as if there’s one Bourne every minute. The latest outing reunites two leading players who swore they were done with the franchise: the actor Matt Damon, looking as bulky and implacable as a tank, and Paul Greengrass, the British director who whipped up a storm in films two and three but consigns it to a teacup this time around.

Rarely has such a fast-paced film felt so weary and resigned. Christopher Rouse’s screenplay throws into the usual paranoid, dystopian, NSA-fearing mix a Zuckerberg-style social media guru (Riz Ahmed) in cahoots with the craggy CIA overlord (Tommy Lee Jones) hunting Bourne. There is also a bright CIA underling (Alicia Vikander) experiencing vague pangs of conscience from her operations hub where po-faced automatons tap endlessly on keyboards; it’s like a Kraftwerk gig without the tunes.

The film makes gestures towards political topicality. But whether it’s riots in Greece or the ongoing tension between security and privacy, everything is reduced to the level of window dressing while Bourne crashes motorbikes, plummets from the tops of buildings and doles out upper cuts as though he were passing around Tic Tacs.

Just once it would be nice to have some character detail or a line of dialogue that went beyond “Suspect turning left”, or the series catchphrase: “You don’t have any idea who you’re dealing with!” Bourne himself is a dead end, dramatically speaking; he has recovered his memory now but his personality and inner conflict have been wiped clean. When he isn’t fighting, he has nothing to do except go woozy with flashbacks and generally outfox the CIA. He should try hiding in the voluminous bags beneath Tommy Lee Jones’s eyes – they’d never find him there.