Formulaic perhaps as a superhero origin story, but packed with smart humour & fun character work, Ant-Man is a thoroughly unpretentious and entertaining edition to the Marvel Cinematic Universe.

Fans were up in arms when Edgar Wright (Shaun of the Dead, Scott Pilgrim Vs The World) left the project citing “creative differences” just before cameras were due to start rolling on Marvel’s first new hero entry in its canon since Captain America: The First Avenger. Peyton Reed (Bring It On, Yes Man) was swiftly brought in to take the reins, while Adam McKay (Anchorman, Step Brothers) was hired to revise Wright and Joe Cornish’s script, together with lead actor Paul Rudd.

A lot of time is spent establishing Stephen Lang and his numerous relationships and interests – his estranged family, devoted daughter, despairing ex-wife (Judy Greer) and her new man, cop Bobby Carnavale; his shady, yet somewhat Robin Hood-esque past as a cat burglar, which he’s trying to shake off despite the best efforts of his old cronies, led by an endearing Michael Pena; and the mysterious new mission, and possible redemption, being dangled in front of him by Dr Hank Pym (Michael Douglas) and his daughter, Hope (Evangeline Lily).

As a result of all this emotional and motivational setup, there are a number of issues left unexplained. The film opens in 1989, with a younger Pym (a convincingly cg-ed Douglas) refusing to hand over his “Pym Particle” to Howard Stark (John Slattery). We learn that Pym has already seen combat as Ant-Man but refuses to relinquish the tech. What is not explained is what Pym then spends the next 25 years doing and how he has kept his tech secret, especially considering it’s been in his basement the whole time. Also, why did Hope side with Darren Cross (Corey Stoll) to vote Hank off the board of his own company?

Cross’ villain is woefully underdeveloped, in a fate suffered by many Marvel antagonists. Cross is little more than a frustrated subordinate lacking a moral compass, who sees the financial benefits as outweighing the potential risk of selling Pym’s shrinking tech to a menace like Hydra. Speaking of which, the Hydra stooges here are little more than guys in suits and the global threat is simply the notion that their attaining the Pym Particle would be bad.

Elsewhere Ant-Man is actually pretty strong. The character’s ability to shrink even as his strength increases relatively, coupled with an ability to communicate with his six-legged insect friends, seemingly makes him the perfect thief, rather than warrior, and his missions are often heists – “breaking into a place and stealing some shit” – rather than conventional crimefighting. When one of those places is revealed to be Avengers headquarters, the perfect opportunity arises for the now obligatory cameos from established team members, and the moment is handled well.

Where Ant-Man differs from recent MCU outings like Age of Ultron and Winter Soldier is that Reed & Co always go for the laugh, rather than the spectacle, which makes a refreshing change. Rudd has built a career on his comedic charms, and cooks up convincing chemistry with both Douglas and Lily, while their relationship follows the familiar yet satisfying path from prickly to passionate. It is Michael Pena, however, who earns many of the film’s best laughs, particularly when the film employs a theatrical means of reenacting his frequent anecdotes that smacks of Wright’s comedy stylings.

Fans of the ultimate Ant-Man precursor, Jack Arnold’s The Incredible Shrinking Man, should appreciate the film’s efforts to explore the sub-atomic dimension. Dubbed here “The Quantum Realm”, the dangers of shrinking too small, to a size where the very physicality of a recognisable reality becomes distorted, are Ant-Man‘s equivalent to “crossing the streams” and holds tragic grievances for the Pym family that Hank is reluctant to revisit. Beyond that, however, the film actually seems less interested in exploring what changes when its characters get small, beyond a good joke involving a toy Thomas the Tank Engine train set that was partially glimpsed in the trailer. There’s also a nice gag for fans of goth band The Cure, which is surely another preserved Wright moment.

While Ant-Man has limited opportunities to advance the larger MCU storyline, it certainly acknowledges it, even cueing up a few interesting developments for the series going forward in its two end credits sequences. Most of the time, however, Ant-Man gets by on its wit, charms and warm personality, for which the Marvel superhero series has been praised since its outset, but has been somewhat obscured in recent outings by its grander world-building efforts. The result is a welcome change of perspective back to lighthearted basics, and no small amount of fun.