Set during the Second World War, Oscar-winning film The Counterfeiters tells the story of Operation Bernhard.

The Nazi scheme forced concentration camp prisoners to produce highly skilled forgeries of English and American bank notes.

Between 1942 and 1945, 142 inmates — facing constant death threats — forged bank notes worth billions, as well as bonds, stamps and other documents.

The Counterfeiters is based on the memoir of one of those inmates, Adolf Burger, and this weekend he will answer questions from an audience after a showing of the film at The Phoenix Cinema.

Born in Slovakia, Mr Burger was a printer when, in 1939, he began working underground for the Communist Party, forging documents to save the lives of those being persecuted.

After his arrest in 1942, he spent two years at Auschwitz-Birkenau, barely surviving slave labour. There he found out his 22-year-old wife Gisela had been sent to the gas chambers.

In April 1944 Mr Burger was singled out from other prisoners. He and nine others were taken to Sachsenhausen concentration camp and to a top secret forgery workshop.

There conditions seemed luxurious: white sheets, pillows, blankets and lockers for personal belongings.

At Birkenau prisoners lived in filthy wooden huts with no running water, did hard labour and were subjected to daily beatings from SS guards.

Yet there was still the realisation that working there meant certain death.

Mr Burger says: “In Auschwitz and Birkenau it was only my will to live that kept me going: the will to survive all this, to be able to tell how the Nazi criminals treated their opponents and victims.

“Now when I came to bed each night, I had this feeling: ‘Here you are on vacation, but you will not come out alive from this.’ Because it was the biggest secret of the Third Reich.”

By the end of 1944 Burger and his fellow forgers had begun to sabotage the process, deliberately failing to produce adequate dollar notes in the hope it would decrease Germany’s chances of winning the war.

As it turns out, the Nazis’ failure to use the forged notes effectively meant they couldn’t have affected the war’s outcome.

As Allied forces drew closer the forgers were moved to other camps and Mr Burger was finally freed from Ebensee, the last concentration camp to be liberated, on May 5, 1945.

Now 91 and living in Prague, he has spoken to almost 95,000 German teenagers about his experiences.

The film and Q&A are on Sunday at the cinema in High Road, East Finchley, at 2pm. Tickets cost £8 (concessions £6) and are available from the box office on 020 8444 6789.

Proceeds from the screening will be split between the Phoenix Cinema Trust and the Holocaust Education Trust.