Loosely based on the comic strip by José Escobar, this pleasingly old-fashioned Spanish children's adventure from 2013 is finally receiving a well-deserved theatrical release, three years after its UK debut at the 2014 Edinburgh International Film Festival. Directed by Oskar Santos (who has subsequently made the 2016 sequel, Zip & Zap and the Captain's Island), it's a lively and entertaining picture that should prove a hit with children and adults alike.

When mischievous twins Zip (Raúl Rivas) and Zap (Daniel Cerezo) are sent to a remote summer boarding school that strictly forbids fun of all kinds, they quickly form a resistance movement called the Marble Gang – recruiting chubby Filo (Fran García) and tiny, bespectacled Micro (Marcos Ruiz), as well as feisty Matilde (Claudia Vega), the niece of the school's tyrannical headmaster Falconetti (Marshland's Javier Gutiérrez). After one of their pranks inadvertently reveals a treasure map, the gang race to solve the various clues, with Falconetti and his mean-spirited sidekick Heidi (Christian Mulas) hot on their trail.

Rivas and Cerezo make an extremely likeable central duo and their fraternal relationship is nicely handled, particularly when their affection for rebellious Matilde threatens to come between them. Similarly, Vega brings energy and spark to her role, García and Ruiz provide strong comic support, and Gutiérrez is suitably hissable as the gang's one-eyed nemesis.

Santos directs with an obvious affection for children's adventure stories (there are echoes of both Harry Potter and The Goonies) and the witty script is brimming with ideas, while the spirit of Indiana Jones is palpable in the puzzle-solving scenes. In addition, the film is simply beautiful to look at, courtesy of Josu Inchaustegui's colourful cinematography and some stunning set design, as well as the seamless and satisfying special effects work on the various mechanical contraptions the kids encounter on the treasure trail. Utterly charming from start to finish, this is a well made, smartly written family adventure with an infectious sense of fun. Don't miss it.

Selected release from Fri 31 Mar.