The film "Look Who's Back" is an adaptation of a satirical novel by Timur Vermes which has sold over a million copies. In it, Hitler wakes up in modern times, becomes a celebrity and enters politics again.
Vermes has said he wrote the book to lambast what he calls Germans' complacency about the Nazis and highlight his belief that Hitler would have a chance to succeed today, even though the modern German state is constructed to ensure that Nazi tyranny can never return.
The film's director and lead actor said that the time spent touring Germany, shooting footage that has been incorporated into the movie, had opened their eyes and that they had witnessed a shift to the right in attitudes.
"How can it be that so many people react positively to Hitler, accept him?" director David Wnendt told Germany's ARD television.
The film shows actor Oliver Masucci, complete with Hitler's trademark moustache, mingling among crowds of smiling people, shaking their hands, posing for photos with firemen and even tickling pet dogs and goats.
"People quickly forgot that the cameras were rolling and started talking to the man, to open up to him," said Masucci.
Filming took place shortly before the emergence of the grassroots anti-Islam PEGIDA movement, centred in the eastern city of Dresden, which drew tens of thousands of supporters to its rallies earlier this year.
"It didn't surprise us that they took to the streets. This middle class that's shifting to the right, we'd got it all on camera," said Masucci.
The success of the book and media interest in the film reflect a fascination among Germans with the darkest chapter of their history even 70 years after the end of World War Two and the Holocaust.
Documentaries regularly run on television and in the last decade or so some taboos about Hitler have also been broken with films such as "Downfall" which chronicled the dictator's last days.
The new film also comes at a time when Germans are being scrutinised for their attitudes towards foreigners, with many Germans worried about the cost and social impact of the arrival of hundreds of thousands of refugees this year alone.
The striking posters for the film, a plain white background with only Hitler's black hair with a side parting and the title of the film ("Er ist wieder da") compressed into a square moustache, are adorning Berlin billboards.