Anyway, one night the brothers investigate a flood, which is never explained, and find a magical pipe, which is also never explained. The pipe zaps them both to another planet, or possibly another universe. That’s never explained, either. Mario is deposited in the fairy-tale Mushroom Kingdom, where cheerful talking fungi are led by a Barbie-like blonde called Princess Peach (Anya Taylor-Joy). But poor Luigi is captured by the monstrous Bowser (Jack Black), who has a name which suggests that he’s a dog, and a physique which suggests that he’s a dragon, but who is actually the leader of a race of turtles called Koopas. By a remarkable coincidence, the brothers arrive on this surreal planet (or, possibly, in this surreal universe) just after Bowser has just got hold of a glowing star which will enable him to conquer Mushroom Kingdom.

To the untrained eye, it looks as if he and his army are so strong that they could have conquered it, anyway, but never mind. The Super Mario Bros Movie has the kind of baffling, nonsensical mythology you might expect when a Japanese game company creates an Italian-American plumber from Brooklyn, and then keeps developing that character’s adventures for 40 years. As long as you don’t worry about it, and embrace the psychedelic randomness, you can accept it as silly, what’s-not-to-like science-fiction. But after a few scenes, this bamboozling plot outline is the least of the film’s problems.

The trouble starts when Mario is suddenly surrounded by floating bricks, giant gold coins, “Power Up” cubes, and burbling electronic sound effects, which only make sense in the context of a video game. It becomes clear at this stage that the directors have given up on making a cartoon which anyone might enjoy, and have concentrated instead on piling on references for the benefit of the games’ devoted fans.