Children’s movies are brilliant. They’re the first experiences of cinema that many kids have, introducing you to a world where anything’s possible. I fell in love with going to the cinema after I saw Chicken Run for the first time when I was six, and even now films aimed at younger audiences, from Moana to Ponyo and My Life as a Courgette continue to delight and inspire me. Captain Underpants, well, not so much.

Whilst the film features a who’s who of Hollywood comedy royalty, from Kevin Hart to Ed Helms, they’re wasted on this bland cash-in on the popular book franchise – you can hear them now in interviews, saying how nice it is to be in a movie their kids can watch. Only Nick Kroll really had a chance to shine as the nefarious Professor Poopypants, and he did ham it up magnificently, but when your villain is better than your hero, you’ve got a problem of The Dark Knight proportions.

But the worst of it is this: Captain Underpants: The First Epic Movie is silly. Just, really, really silly. Sure, kid’s films are allowed and even encouraged to be silly, just take the excellent Cloudy with a Chance of Meatballs – but there’s this sense of aggressive wackiness about Captain Underpants which makes it really hard to enjoy if you’re past the stage of finding fart jokes funny. Kids might like it, but it’s not a film that will be passed down in the great lexicon of children’s cinema. Not even in the lexicon of great underpants-wearers in cinema (title still held by Michael Keaton in Birdman.)

The plot is weak, the lead characters are anything but endearing, and there’s this sense we’ve seen it all a hundred times before. The animation style is jarring too, similar to that of The Peanuts Movie, halfway between drawing and animated, and failing on both accounts. The film would have looked infinitely better as a cartoon – there was a pretty neat mixed media sequence near the start which hints at this. Perhaps it would even work better as a television series – ninety minutes feels like quite a lot for even the most patient child to endure.

The book series might have sold millions of copies and sparked a love of reading for many youngsters, but this is a sub-par transition into film. Dreamworks can do better, we’ve all seen it, and perhaps there are some books that just don’t need to be translated onto the big screen, no matter how tempting the merchandising rights. I suppose there’s only so much you can do with a character whose schtick is being able to throw Y-fronts at people, after all.

Captain Underpants: The First Epic Movie is released on July 24th.