Film review: Oz the Great and Powerful - You thought the Wizard should be left alone? Step this way …

So, how did Oz gets its Wizard? This question has never exercised me for more than a nanosecond, but as redundant as Oz the Great and Powerful might seem, this Disney prequel turns out to be something of a classic: a family friendly fantasy which delivers as an affectionate prologue to The Wizard of Oz, that works just as well as a spectacular, neatly structured stand-alone adventure. It's directed by Sam Raimi, who once again brings irresistible enthusiasm to cartoonish genre entertainment, but it could also pass for the best Tim Burton film in a long time, and the best Terry Gilliam film in even longer.

It opens (in black-and-white, of course) in Kansas in 1905, where a second-rate fairground magician (James Franco) is as intent on fooling local beauties as he is on fooling his meagre audiences. Soon, his hot-air balloon is whisked by a cyclone to the story-book world of Oz, a Technicolor wonderland which, along with the alien planet in Avatar, is one of the few settings to justify the use of CGI and 3D. After Franco crash-lands, a good witch (Mila Kunis) mistakes him for the sorcerer who has been prophesied to save Oz from her wicked cousin (Michelle Williams). But maybe, just maybe, it's her sister (Rachel Weisz) who's really the wicked one. She does have an English accent, after all.

I'm not sure whether Franco has the stature to carry a whole film on his shoulders, but there's no doubt that he nails the screenplay's well-judged humour. Unlike half of today's children's films, Oz the Great and Powerful is funny enough to appeal to accompanying adults without undermining the sincerity of its emotions or the excitement of its action sequences. And unlike the other half of today's children's films, it's content to be bright and cheery rather than trendily grim. It's one prequel that deserves a sequel.

Robot & Frank (Jake Schreier, 89 mins, 13A ****) stars Frank Langella as a retired jewel thief who now lives in leafy seclusion in upstate New York, sometime in the "near future". Concerned by his ailing memory, his son (James Marsden) buys him an android valet/nurse (voiced by a deadpan Peter Sarsgaard). At first, Frank isn't happy with his cyber-babysitter, but when he discovers that the robot's programming doesn't preclude it breaking the law, he decides that a return to the burglary business might give him just the mental and physical work-out he needs.

It won't set any pulses racing, but Robot & Frank develops into a touching yet unsentimental buddy movie, with a humdinger of a twist and some sly satirical digs at yuppie hipsters. And how nice to see a sci-fi film that doesn't require armies of computer-generated monsters, just one boxy, white plastic Jeeves.