His extraordinary account of surviving the Holocaust came back to me on Sunday, along with other amazing accounts from that period after I watched German film Phoenix.

Set in the bombed-out streets of West Berlin, Phoenix - which opens in cinemas on May 8 - tells the astonishing story of a young Jewish singer, Nelly Lenz, attempting to reclaim her life and husband after suffering a gunshot wound to her face in a concentration camp.

After successful reconstructive surgery, she locates her non-Jewish husband - who may have betrayed her to the Nazis - and attempts to re-enter his life without revealing her true identity.

Unlike Tirosh's story, the plot of Phoenix, directed and co-authored by Christian Petzold, is fictional.

Ignoring the limitations of plastic surgery in general and in the 1940s especially, it compromises its credibility on this and a number of other points to discuss its main theme - the effects of emotional, physical and even social trauma on one's identity.

The film conducts that discussion in a subtle, comprehensive and engaging manner, largely thanks to what many film critics have praised as excellent acting by Nina Hoss, Nina Kunzendorf and Ronald Zehrfeld.

But walking out of the film on Sunday, my mind wondered back to the story of Tirosh and other eyewitnesses to real-life events during the Holocaust.

People like Johan Van Hulst, the 104-year-old war-time saviour of dozens of Jewish children who fixed me a cup of coffee at his Amsterdam home before recounting his actions in fine detail.

And my own grandmother, who fell through the Nazi death machine's cracks thanks to a series of incredible twists of fate.

As these witnesses quickly disappear from our lives, I wonder about the merit of a fictional film about the genocide - itself subject to revisionism - with a plot that rivals the works of Pedro Almodovar.

Obsessed with documenting the Holocaust through testimonies, the journalist in me has reservations about films like Phoenix or Ida, whose fictional plots are almost realistic enough to pass for plausible in the sea of unlikely but authentic survival and rescue stories.

But another part of me is prepared to see slippage in accuracy in Europe's ongoing debate about the Holocaust, if it comes with the deep reflection and observations about European societies and their Jews demonstrated in films like Phoenix and Ida.

Petzold got the idea for Phoenix from Filmkritik magazine, which "included an article by Harun Farocki called 'Switched women'.

"One of the examples he cited in his essay was a book by Hubert Monteilhet called Return from the Ashes, on which the film draws.

"When I met Harun, we spent a lot of time talking about this book. We asked ourselves whether, perhaps, a story like that - a kind of mixture between Vertigo and returning from the concentration camp - could only be told in France.

"And that's when we started thinking about German post-war cinema - why it is that we have no comedies or genre films? - and the idea that National Socialism created an abyss into which you're thrown again and again."

Hoss, who plays the lead character, said she realised there were few accounts of life after the Holocaust.

"Nelly comes out of a concentration camp - she's survived, she's been saved," Hoss added.

"What's that like when you're still in the middle of that trauma? What kind of condition are you in? Can you even talk about your experiences yet? For me, that was a defining point.

"When we meet my character, what condition is she in and how close might she be to insanity? In the camps, you were 'dehumanised': They tried to destroy everything that made you human.

"How can you then re-connect with the things that defined you as a human?

"It became clear to me why Nelly has to keep hold of this fixed idea of Johnny. If he recognises her, that means she's alive again.

"For me, it wasn't about asking, 'Why doesn't he recognise her?' - after all, she doesn't recognise herself. If you've been broken to the core, then you no longer recognise yourself. I had to get my head around that."

Additional reporting by Mike Cohen