As Marvel comic superheroes go, the Ant-Man is one of the strangest – a superhero in a suit who shrinks to the size of an insect but expands internally in strength. Movie adaptations of Marvel’s vigilantes have emphasised scale in every possible way, with the Iron Man and Avengers franchises taking this obsession with swagger and its corresponding machismo to migraine-inducing proportions.

Peyton Reed’s Ant-Man is, by the very nature of its subject, a smaller and consequently far more enjoyable enterprise. The 118-minute movie retains a cheerful and light comic-book tone throughout, with its highlight being a battle for supremacy waged on a Thomas toy engine set between two miniscule men in insect-themed suits.

It all begins slowly and predictably. Good-hearted cat burglar Scott (Paul Rudd) is hand-picked by genius scientist Pym (Michael Douglas) to slip into the superhero suit that shrinks its wearer in inverse proportion to his powers. Ant-Man has an evil twin in the form of the Yellowjacket, which has been created by Darren (Corey Stoll), Pym’s former protégé gone rogue. The screenplay contrives to explain why Pym doesn’t allow his daughter Hope (Evangeline Lilly) to become an Ant-girl and destroy Darren’s malevolent creation even though she is perfectly skilled to do so, but there’s a simpler explanation to be found in this old-fashioned fantasy adventure. Hope is routinely referred to by Scott’s crackpot cohorts, including the talented Michael Pena, as a “pretty lady”, and she plays her part to the hilt.

There’s another unnecessary to-do about smuggling the Ant-man and his teeny drones into the facility where Darren has concealed his Yellowjacket. Since these creatures are barely visible to the eye, could they not have sneaked in anyway? As far as excuses for rolling out visual effects go, this has to be one of the poorest.

The contrivances and on-the-clock rollouts of humour and spectacle pass since Reed keeps his ambitions low. A suburban home rather than a city is ravaged in Ant-Man and the skyline remained unmolested, but the mandatory post-credits sequence suggests a bigger role for Ant-Man in future editions. This movie keeps boredom at bay through simply sketched characters and judiciously dispensed visual effects, but while the future looks bright for the endlessly expanding billion-dollar Marvel franchise, it has already dimmed for some of its intended recipients.