Time was you knew where you were with Tom and Jerry. He chases the mouse; catches the mouse; the mouse gets away; Tom is flattened, gets up dazed but determined; and then it’s back to the chase. The tone changed over time – Tom was originally more scary than he became later – but essentially the fun was in the rivalry that would never cease; the plot’s piquancy was that of David and Goliath, the little mouse always getting the better of the big cat.

I can only hope the Chinese audience buys it because I couldn’t

But the old Hanna-Barbera scenario that began in 1940 has evolved and the franchise has passed into new hands. Now a little cartoon that once lasted only a matter of minutes has turned into a 3D, computer-animated, 90-minute blockbuster, Tom and Jerry: Forbidden Compass. It’s a Chinese-American production, and directed by Zhang Gang, and the premise finds the pair accidentally transported back in time to ancient China. If there’s one thing that you could say about the old T&J, it’s that it was all-American. What we get here instead is a weirdly dissonant hybrid. I can only hope the Chinese audience buys it because I couldn’t.

It starts off in the old style, with Tom as a security guard keeping the mouse out of the museum with a chase round and round the artefacts – but it turns portentous very quickly. A backstory booms out that there’s an enormously powerful thing on display called the Forbidden Compass that everyone has forgotten how to work. But hello… Jerry has managed to squeeze himself into the electric light. And now Tom is switching it on and off, and the current has got into the compass, and bingo, it’s sizzling with power and we’re in ancient China.

I wish I could tell you what the plot was after that but I couldn’t make it out. It was like the time I went to a Chinese opera – all noise, bangs and scary masks, but no tunes or obvious story. Here we find a handsome Chinese bloke accompanied by a cartoon chicken. He is, it seems, a deity who has been kicked out of heaven by an even bigger deity with enormous cloud-like hands. He can only get back to heaven by securing the compass. And so he’s on the trail of Tom and Jerry – who have the compass.

But look, there’s also an evil King Rat with horrible hench-rats, who are also after the compass for their own terrible ends. He has a mechanical tail with a snapper thing on the end. As a group, they have the depth of the King Mouse gang in The Nutcracker, who endlessly point and jeer but never really do anything. An endless pursuit ensues, with the King Rat after Tom, who is also being pursued by the handsome deity. Confusingly the deity is supported not only by the weird-looking chicken but also by three little gargoyles, all of whom seem to have been designed to look like merchandise, especially the unicorn.

Philosophically the film is very Chinese in spirit, for the deity, it seems, has to win enlightenment before he gets back into heaven. And enlightenment will only come if he stays on Earth to help others. Meanwhile, the King Rat, after sinking to the bottom of the sea and tearing down a few temples with his bare claws, is overcome by the strength of true friendship and ends up as a tiny little rodent.

Look, if this is all that computer animation and AI has to offer, we don’t have anything to worry about. It’s like being trapped in a very bad video game,  with endless chases that go nowhere and lots of explosions and coloured smoke to make up for the want of plot. And we never do get to find out what the bloody Forbidden Compass does.