"Artnapping” is when museums, insurance companies or private owners are blackmailed into paying millions of euros in ransom for the safe return of their belongings. These artworks can be hard for the authorities to track down. Take the case of the methodical thieves who robbed Dresden’s famous Green Vault museum: In November 2019, two burglars broke in to the Dresden Castle. They stole historical treasures and fled, long before the police arrived. More than 100 suspects have been arrested. But the royal jewels the thieves took from the glass displays that night? They’re still missing. In 1994, two paintings by the British artist JMW Turner were stolen from the Schirn Kunsthalle in Frankfurt. After eight years and many detours, the pieces were returned to the Tate Gallery in London. But to get these prized possessions back, the museum had to make a deal with the robbers, paying five million euros in ransom. To this day, the people behind the crime remain unknown — and unpunished. Boris Fuchsmann, on the other hand, has given up on ever finding his treasure again. The millionaire from Düsseldorf used to own one of the largest coins in the word. The "Big Maple Leaf” was made of pure gold and weighed 100 kilograms. The art collector loaned his coin, worth 3.7 million euros, to Berlin’s Bode Museum, where it was stolen in 2017. The robbers were found, but the coin is still missing: police suspect it was cut into pieces and melted down, as state investigators found gold dust on the thieves’ clothes. These are among the world’s most spectacular cases. But they are probably only the tip of the iceberg, says Stefan Koldehoff, an art market expert and non-fiction writer specialized in art theft. The journalist believes the number of stolen artworks is far higher than official numbers show. After all, while prices on the art market have been skyrocketing for years, making looted artwork all the more valuable, the security systems at museums have grown completely outdated.