There is something melodramatic and soapy about this glossy adaptation of Michael Morpurgo’s second world war novel for children, the story of a French boy who helps to save Jewish children by smuggling them over the mountains into Spain. The problem, I think, comes from a fear of upsetting its target audience of older kids (the film has a 12A rating). So the tough bits are fuzzily done – at arm’s length and hurried over – making for an oddly flat unemotional watch. The accents don’t help: the actors all speaking English dialogue with ’Allo-’Allo accents (with Jean Reno thrown in for a bit of Gallic authenticity).

The setting is occupied France. In the Pyrenees, teenager Jo (Stranger Things’ Noah Schnapp) discovers that mean old lady Widow Horcada (Anjelica Huston) is in fact heroically hiding Jewish children on her pig farm. Huston does her best with a thin character, but even she struggles with the starchy dialogue: “Some people collect coins or stamps. We collect enemies of the Reich.” Widow Horcada is also harbouring a Jewish man, Benjamin (Frederick Schmidt), who has become separated from his young daughter, Anya. Reno plays Jo’s grandfather, a salty first world war veteran who marches around the village wearing his army medals in proud defiance of the occupying force.

The film is gorgeous to look at, all alpine meadow flowers and glorious green mountains. But the drama loses momentum pretty early on. When the Nazis grow suspicious of Widow Horcada, her resistance gang must decide: should they risk one last journey over the mountains? Schnapp, with his lovely innocent open face, carries it all so far. But the film pulls its punches, awkwardly rushing through difficult scenes, such as the one involving a sneering sadistic German officer performing a mock execution on a teenage boy with learning difficulties. Kids may feel they’re owed more honesty. What a soggy mess.

• Waiting for Anya is released in the UK on 21 February.