Anton Ego, the restaurant critic of The Grim Eater, is one of the greatest performances of Peter O’Toole’s career. We don’t actually see the 108-year-old Oscar hopeful in the flesh. But we luxuriate in his withering voice. And what a tool that is when it is coupled to the creep he possesses in Brad Bird’s marvellous cartoon Ratatouille. Ego is the most feared food critic in Paris. His office is shaped like a coffin. In fact he’s shaped like a coffin, and his deadly words drive chefs to their graves. I haven’t enjoyed a painted villain this much since George Sanders’s Shere Khan.

It takes a lifetime to learn how to deliver a fatal insult, and O’Toole has had at least three. He is the wicked spice in a film with the most implausible brief since Elvis returned from Mars. The real hero of this preposterous kitchen fable is a cashmere-blue rodent called Rémy, who has the culinary genius of Raymond Blanc, and the misfortune to look like a rat. He is a rat, but he walks on his hind legs and speaks with a neurotic Woody Allen twang. He is horrified by the junk that his friends and family scavenge from dustbins, and he would doubtless campaign for the abolition of rat poison in junk food if he was 5ft 2in taller and called Shamus Oliver. This Pixar fairytale is so brilliantly painted that you give up caring whether it makes the slightest bit of sense. This is the wonderful point of Bird’s film. Ratatouille is an extraordinary demonstration of just how close animation can get to touch, smell, taste, and what the world might look like through a pair of rat’s eyeballs.

Rémy (plaintively voiced by Patton Oswalt) is obviously not a bog-standard representative of vermin. He doesn’t understand why humans shriek at the sight of him. And he has an insane dream – augmented by the ghost of a fat chef (skewered by one of Ego’s reviews) – that he can become a cook in a prestigious restaurant. But Rémy’s 2in-tall views of cobblestones, puddles, gutters, drainpipes and rooftops are the real miracles in Ratatouille. I’ve never experienced a film that could evoke flavour. This reeks of Paris.

The plot doesn’t flatter the sensational art. It does at least have the grace to send up its own utter silliness. Rémy befriends a clumsy and gawky kitchen boy, Linguini (Lou Romano), who hides the rat under his chef’s hat. The unlikely duo devise a string of winning dishes, which puts them on a collision course with a jealous, pint-sized head chef (a Hispanic version of Shrek’s Lord Farquaad), the local health and safety inspector, and of course the dread critic of The Grim Eater.

U, 117mins

Editor's choice

• Vote for the Breakthrough Award winner
• David Tennant back as Hamlet after back surgery
• Matt Smith is the new Dr Who