Imagine one day you decide to take that old painting in your living room to an auction house. The expert there values it at around €1,500. And then imagine that 24 hours later it’s worth €300 million. You suddenly realize this apparently valueless painting is going to revolutionize the art world. Well, that’s what happened to an 80-year-old woman from Madrid on 8 April 2021. From that day on, the events that followed are packed with all the elements of a real-life thriller.