A day later he and Eva boarded a U-­boat, which was the signal for their doubles in Berlin to be executed.

Under heavy Russian gunfire their remains were incinerated in the garden. 

By the time the Russians reached Hitler’s bunker and found the fakes their real prey was deep beneath the atlantic Ocean.

The most audacious ruse in history was complete and it is claimed that Hitler spent his remaining 17 years living peacefully in a Nazi enclave in Argentina. 

A fortune in looted gold and jewellery, loaded on to the submarine during the escape, ensured that he wanted for nothing.

Gerrard Williams, a journalist and film director, says: “There is no forensic evidence that Hitler died in the bunker. The Nazi high command had been making plans since 1943 to get out of Germany and to set up a Fourth Reich, mainly in South America, so they had no need to die in Germany. There was a very effective route out of the country.

“We never wanted this story to be true but the horrifying reality is, we believe, that at the end of the war the most evil man in the world escaped from Germany and lived out his life in Argentina.”

It is known that Argentina was sympathetic to the Hitler regime – even supplying fake paperwork to help them escape from Europe – and became a haven for many prominent nazis after the war, evil men such as Josef Mengele, Adolf Eichmann and Klaus Barbie. 

The entire plan is claimed to have been masterminded by Hitler’s private secretary Martin Bormann and “Grey Wolf” was the codename for the Nazi leader.

The soviets always gave conflicting information about the discovery of the bodies in the Führerbunker and what happened in the chaos of the end of the war. 

The remains were said to have been buried but later exhumed and moved to different locations, apparently to avoid Hitler’s grave becoming a shrine.

However it later emerged that the Russians kept a piece of his skull with a distinctive bullet hole. The fragment was always said to be incontrovertible proof that Hitler had indeed died by his own hand in 1945.

Then two years ago archaeologist and bone specialist Nick Bellantoni concluded that the skull really belonged to a woman aged under 40 and not Hitler, who was 56 when he supposedly died. 

Bellantoni also dis­ counted the possibility that the skull was that of Braun because she was said in reports from the bunker to have killed herself by taking cyanide and would therefore not have suffered a bullet wound.

Intriguingly, declassified FBi files from the late Forties also contain a reference to Hitler having escaped Berlin and begun a new life in South America. 

For almost 30 years J Edgar Hoover and his FBI maintained a detailed dossier on the Nazi leader and investigated any report that indicated he still was alive, including dispatching agents to Argentina on several occasions.

When US president Harry S Truman asked Joseph Stalin in 1945 whether Hitler was dead, the Soviet leader is said to have replied bluntly, “No”. 

As late as the Fifties US president Dwight D Eisenhower declared: “We have been unable to unearth one bit of tangible evidence of Hitler’s death.” 

At the end of the war the death of Hitler was a neat conclusion. It was not surprising that the world lapped up the stories of his suicide without asking too many searching questions.

Williams, who spent five years researching the book and made numerous visits to Argentina, says: “Everyone wanted to close the chapter very quickly because the Cold War was just starting. It’s only now Argentina is once more a thriving democracy that the real stories are coming out. The more files and reports we looked at, the more we realised the death in the bunker was a fiction.”

The book includes testimony from the pilot who “flew Hitler and Eva Braun out of Berlin” and a dozen other witnesses.

According to the book 53 days after leaving Spain by submarine the couple arrived off the Argentine coast, south of Mar Del Plata. The Führer and his mistress were quietly but enthusiastically welcomed.

Hitler would live there in a village in the foothill of the Andes until 1962, planning the rebirth of the Nazis. It is claimed that he and Eva did marry but separated in 1953 when she moved to Nequén.

The book also contains the testimony of bodyguards, cooks and doctors who claim to have worked for Hitler. The authors say they have evidence that pinpoints the exact house where he lived in Patagonia. A rather grand wooden chalet-style building, it must have reminded Hitler of the Bavarian Alps.

The Führer is claimed to have died on February 13, 1962 at 3pm. He was said to be demented but still clinging to his dream of Nazi domination.

There is a chilling postscript revealed in the new book. Before they separated Adolf and Eva are claimed to have had two daughters. According to the authors both are still alive in South America.

If this account is to be taken seriously Hitler’s bloodline survives with them.