Tom Cruise has become an overnight hero in Germany thanks to his film about the plot to kill Hitler — a story the German authorities fear could become a propaganda vehicle for Scientology.

The country’s critics, initially sniffy about Valkyrie, a portrayal of Count Claus Schenk von Stauffenberg, the army officer who tried to blow up the Führer, are now giving Cruise a thumbs up — or at least a verdict of “not bad for a foreigner”.

If the film becomes a hit — and early signs are that the public like it — some police and politicians are worried that it will give Scientology, of which Cruise is a leading member, a boost in Germany.

The German equivalent of the Special Branch, the Agency for the Protection of the Constitution (BfV), believes that Scientology is an antidemocratic organisation and is keeping it under close observation.

“These Scientologists have two goals in Germany,” said an official close to the BfV. “To get their message to children, and make their organisation respectable. The film does both: it has put a top Scientologist at the centre of a national debate about German history. That’s dangerous.”

Michael Brand, a Christian Democrat politician, has appealed to his fellow deputies to call for a boycott of Valkyrie in their constituencies. “Stauffenberg would have waged resistance against the likes of Tom Cruise,” said Mr Brand, saying that Scientology pursued totalitarian goals.

The BfV, which has a brief to monitor terrorism and extremist groups, says in its latest report: “Scientology shapes the political opinions of its members in a way that makes them hostile to the principles of the Constitution.”

The organisation recently opened a headquarters in Berlin as its main lobbying centre in Europe. Claudia Schmid, the head of the Berlin division of the BfV, said the group was trying to ingratiate itself with the political class.

As long as the numbers of fully paid-up Scientology members remain small — 6,000 in Germany — Ms Schmid believes that it would be difficult to have the group banned.

“This is not like other Tom Cruise hits,” a BfV insider said. “It’s not Mission: Impossible, which is harmless fun. This is a statement about Germany and I anticipate that as with Downfall [another war film] , schoolclasses will be taken to see it.”

Valkyrie is certainly making an impact on German audiences. Outside the Cinemaxx cinema in Potsdamer Platz in Berlin, Christine Grossmann, a science student, was still under its spell. “I have never seen our history done this way, everything moving so quickly, no big speeches like in German films,” she said.

Cruise has been dodging questions about his Scientology beliefs from his German interviewers. “I’m an actor,” he told the Sueddeutsche Zeitung. “If somebody wants to know about Scientology, let him go into the internet, or go to church, find out for himself. I’m just talking about the film.”

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