Reynard Heydrich, the Butcher of Prague, was assassinated in spectacular fashion in 1942 when a grenade was thrown into his open-top car as it travelled through the streets of Prague.
Undoubtedly the most repellent of Hitler's deeply unpleasant top brass (he was head of the Gestapo and one of the most enthusiastic architects of the holocaust) Heydrich's loss proved devastating.
Additionally, his death was a huge personal blow to Hitler - who affectionately referred to him as "the man with the iron heart"
It was resolved that security must be tightened.
To that end, the Nazi elite commissioned the Aktion P, a heavily armoured Mercedes-Benz 540K that has emerged as one of the rarest relics of the war.
Only 20 were ever produced for the Reichskanzellerie Berlin Motor Pool, of which three have survived to the present day.
Now one is to auction at Bonhams' Goodwood Festival of Speed Sale on June 27.
The story of how it ended up in the sale is almost unbelievable.
After the Soviets captured Berlin, following days of heavy shelling, the city was in ruins but miraculously the 540K had survived despite the near total destruction of the motor pool.
The reds moved in and it disappeared into the East - its fate unknown.
In 1991, the Baltic States found themselves free of the Russian yoke and opened up to the West for the first time since 1940.
It was in this atmosphere of political upheaval that an American buyer found himself in Estonia hunting for unusual relics to sell back at home.
He soon heard about a strange car that had been dismantled and hidden on a farm somewhere out in the sticks. By a stroke of luck, he got talking to some locals who knew of its whereabouts.
They brought him to the farm, where he was shown the parts of the car - which were hidden across several barns.
This turned out to be a precautionary measure; the mafia knew of the existence of a valuable car somewhere in the region and were on the prowl.
The American offered a generous sum of money that the farmer summarily rejected, insisting that he had no use for it and was content as he was.
However, he did have a young daughter who had just started school.
After some consideration, the American offered to get her a place at a school in America in order to improve her future prospects.
A quick phone call on a cell phone was enough to confirm that the girl was eligible for a visa.
Incredibly, he was able to connect the phone to a printer in the middle of nowhere and receive a faxed application form for the school.
In return, the farmer handed over the parts. The car was smuggled out of the country under the cover of darkness and flown to Helsinki and then on to the US, where it has remained ever since.
You can read our preview of the sale here.
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