Many years ago while working on a newspaper story in Germany, I attended a Friday-night service at a synagogue in Munich. The elderly rabbi was a Holocaust survivor who had returned to the city of his birth after Dachau camp was liberated and I kept looking at him and wondering why?

To be mercilessly persecuted by one's countrymen and then volunteer to live among them again made no sense to me, but he was not the only German Jew to make such a choice and Christian Petzold's thought-provoking film-noir-styled Phoenix deals with this notion in a most original way.

Actress Nina Hoss, Petzold's muse, is mesmerising as Nelly, a disfigured Holocaust survivor who returns to shattered post-war Berlin after having her face reconstructed by plastic surgery. This has all been arranged by her friend Lene (Nina Kunzendorf) who works for the Jewish Agency and plans to get them both to Israel after Nelly claims a large family inheritance kept safe in a Swiss bank.

"You are the only one who survived," says Lene offering distressing reassurance, but Nelly is not ready to go as she is still deeply attached to Johnny (Ronald Zehrfeld), her missing gentile husband who was also arrested, but then released. Transformed by surgery Nelly is unrecognisable to her spouse when she eventually finds him, but a passing resemblance to the wife he believes is dead is enough for him to hatch a scheme that will allow them both to claim the money.

Scarred physically and psychologically, Nelly agrees to imitate herself according to Johnny's instructions and he marvels at her ability to copy his late wife's handwriting and pretend to be a survivor. It was the memory of Johnny that enabled Nelly to survive in the camp, but the closer they get to readiness, the more she grows suspicious about his role in her deportation. For the viewer, Phoenix is intensely troubling and the longing to rescue Nelly from her own obsession overwhelms, but understanding her needs is as complex as comprehending the decision of the Munich rabbi. Unless you wear their shoes, you'll never know.