As a teenager he attempted to assassinate Adolf Hitler. Seven decades later Henry Wermuth is busy writing adventure stories, but his own life has been far more dramatic than his fiction.

The Holocaust survivor, who lives in north-west London and recently celebrated his 90th birthday, has just published his third novel, The Rescue of the Murdered Consul’s Children, a tale of revenge set partly in the Wild West.

Born in Frankfurt, he was deported with his family to Poland in 1938. Over the next seven years, he was transferred from concentration camp to concentration camp, including Auschwitz.

Remarkably, he and his father, Bernhard, were together throughout the war, but Bernhard died just days before liberation. “It has haunted me my whole life that there was a possibility we could have escaped,” Mr Wermuth said.

He has never discovered the exact fate of his mother and sister, but it was for them that he mounted an audacious attempt to kill Hitler in 1942.

Mr Wermuth was in a labour camp called Klaj when he heard that the Nazi leader was expected to pass through the town to boost the morale of troops following heavy losses at Stalingrad.

“That night, I smuggled myself out of the camp — in this particular camp it was possible to do so,” he said.

He walked the two kilometres to the station, where he found logs and stones that he placed on the tracks to derail the train. The next morning, he said: “A train passed with three wagons, and in the window was a man who I recognised by the mustache as Hitler.

“I stood there mesmerised, waiting for the crash, but it never came. Either a local farmer or someone patrolling must have removed the logs.”

An account of Mr Wermuth’s experience in the Holocaust, Breathe Deeply my Son, is now in its seventh edition. His bravery was honoured by Germany in 1995 with a medal.

Today he remains about modest his attempt on Hitler’s life. “My mother and sister had been deported, I hoped to free them,” he said. “At the time I was 19 — I didn’t think about the consequences.”