Theo - who was worth $27 billion when he died in 2010 - became a recluse after he was taken at gunpoint by two men and held for ransom for 17 days. The abduction was described as ‘one of the most spectacular crimes of its kind in post-war Germany’.
The supermarket tycoon - who was well known for his thriftiness and drove that ideology behind the budget supermarket chain - reportedly haggled furiously over the $2.7million ransom, which would equate to $17 million in today’s money.
The kidnappers later revealed that Theo would’ve been released a lot sooner had he not spent so long arguing over the ransom amount.
The billionaire later applied for a tax break on the ransom amount, sensationally arguing that it was a business expense.
The kidnapping lead Theo - and his brother and Aldi co-founder Karl - to become recluses in their later years.
Rarely seen or photographed from 1971 to through to 2010, Theo refrained from giving any interviews or statements through that time as well. Bodyguards also say he changed his route home from the office every day to avoid being targeted again.
But in an interesting twist, it later emerged that while the kidnappers - Paul Kron and Heinz Joachim Ollenburg - were arrested and served eight years in prison, much of the ransom still remains missing.
Before he died, kidnapper Kron claimed he was living on a pension and knew nothing of the missing millions.
“Honestly, I don’t know [about the missing money],’ he told Bild magazine. ‘I only got 10,000 deutschmarks from Ollenburg. He was cleverer than me.’
Conspiracy theories have continued to rage stating that the money had been stashed in Switzerland. The money - which was tagged - still has never been found.
‘It is one of the world’s great mysteries,’ said a local paper.