The proscribed cineaste description of the new Tarantino film is Plantation Spaghetti Western, a knowing fusion of three exploitation genres that were popular around the turn of the 1970s – Mandingo, Blaxploitation and the sub-Leone Italian Wild West tales.

I prefer to think of it as a 21st century Blazing Saddles. Instead of Gene Wilder and Cleavon Little, we have Waltz and Foxx, a black and white pair causing mayhem as they stand against intolerance and bigotry.

Christoph Waltz is Dr King Schultz, an erudite and supremely self-confident German bounty hunter. He's a typically contrary Tarantino creation – a loquacious gunslinger in a profession that generally favours the taciturn and a German champion of racial equality.

Jamie Foxx is Django, a slave who Schultz frees along the way and trains up in the bounty hunting trade. After some initial awkwardness adjusting to his freedom, Django quickly re-emerges as an assured figure of Nubian cool and the pair go off to rescue Django's wife (Kerry Washington) from Candyland, a plantation run by Leonardo DiCaprio.

Unchained is full of the stuff that Tarantino does best – exaggerated violence, genre subversions and tense lengthy dialogue scenes that flirt with outstaying their welcome.

It's a fun romp – though it doesn't quite have the bracing thrill the very best Tarantino films have. The first hour is particularly light-hearted and the sequences involving the Ku Klux Klan really could have been the work of Mel Brooks. Of course, Blazing Saddles was far more provocative than this.

For a film about race, it is comparatively anodyne. It is also too long and doesn't have the imaginative casting coups that his other films have.

However entertaining Waltz is, this performance is what we have already got accustomed to seeing from him. The only performance that catches you off guard is Tarantino regular Samuel L Jackson as an aging house servant. It's a showy, even gimmicky, performance but hugely effective. He's like the young David Jason playing Blanco in Porridge — though 64-year-old Jackson isn't much younger than the character he plays.

Tarantino made his mark as a director of yap films, talky pieces like Reservoir Dogs and Pulp Fiction before trying his hand at action with the Kill Bills. The two Bills weren't always the most assured of creations and, at times, his desire to homage the films of his youth felt like a conscious rejection of what made him special. Now audiences are seeing the benefits of his Grindhouse diversions – it has resulted in a fuller vision.

DJANGO UNCHAINED (18)

Director: Quentin Tarantino

Starring: Jamie Foxx, Christoph Waltz, Leonardo Dicaprio, Kerry Washington, Samuel L. Jackson and Walton Goggins

Length: 165 mins

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