German politicians have been urging foreign residents to integrate more deeply into society — and so Kwami Ogonno, a Somali, decided to do his bit.

He tried to rent an apartment, join the local allotment community, stay the night at a campsite and apply for a hunter’s licence — a fair introduction to mainstream German society. But at every juncture he was blocked, and often rudely rejected.

Kwami Ogonno is, in fact, Günter Wallraff — one of Germany’s top investigative reporters — and he has now made a film, Black on White, and written a book about his expeditions into the country’s racially prejudiced undergrowth.

Blacked-up and wearing an implausible Afro-style wig, Mr Wallraff’s first point was quickly apparent: that the Germans are so unaccustomed to seeing black faces in everyday life that they cannot distinguish his not-very-convincing caricature from the real thing. The result is, if anything, more revealing than Sacha Baron Cohen’s fictional character Borat — supposedly a Kazakh reporter — who exposed bigotry in the US.

One of Kwami’s first destinations was a guard-dog training centre in Cologne. Kwami explained that he would like to train his dog to defend him from skinheads, but the owner of the centre took one look at the pseudo-Somali — whose skin colouring involved two hours of spraying — before blurting out: “Sorry, no places left on the course.” When Kwami persisted, the owner cited an absurdly high sign-up fee of ¤250 (£226). A voice could be heard off-camera saying: “And those rates are about to go up!”

Kwami gave up, but Mr Wallraff’s secret camera team remained in place long enough to film a white German trying to enrol shortly afterwards — and being accepted immediately, and charged the usual fee of ¤60.

Mr Wallraff has been criticised by some African residents in Germany who say that the film, which went on general release yesterday, is a portrait by a white man who cannot begin to understand the emotions stirred by social rejection. “He can’t claim to be a spokesman for black people,” says Sven Mekarides, head of the Berlin Africa Council which, among other things, chronicles and arranges legal support for victims of racist attacks.

Mr Wallraff — in contrast to many African immigrants, especially in eastern Germany — was only once seriously threatened with physical violence, when he tried to get on a train with football fans from Dynamo Dresden football club. “In real life you would have to be tired of life to do that,” says Mr Mekarides.

Mr Wallraff made his reputation as an undercover reporter in the 1980s, when he disguised himself as a Turkish steelworker and chronicled discrimination in a plant on the Ruhr. His other roles have included working a stint as a reporter for the mass circulation Bild newspaper to expose its journalistic shortcuts and, more recently, infiltrating a call centre. His latest odyssey will stun Germans, who consider themselves to be a tolerant society.

The reporter’s unsuccessful attempt to rent an apartment will strike a chord with many foreign residents who don’t have white skin. One potential landlady, having made an appointment with Kwami by telephone, declared the apartment to be taken as soon as she saw him in the flesh. As he left, she was secretly filmed saying: “Really black, really bad”.

The reporter, accompanied by two black women friends, tried to stay at a campsite in Minden, northern Germany. “No space,” he was told, with the manager commenting out of earshot: “The skin colour is the problem.” There were positive moments. In a Bavarian pub, for example, he was protected by two customers from threats — but this was a rare occurence.

Philipp Lichterbeck, film critic for the Tagesspiegel newspaper, says that Mr Wallraff’s disguise made him look like a clown. The fact that nobody suspected that something was amiss, he says, “does not exactly testify to the worldliness of the Germans”.

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