Imagine if you had some old painting that's been hanging up in your family's home all of your life. You know a little bit about it, but stuck it behind a door. Then you took it to an antique dealer and found out it's worth a whooooole lotta money!

That's exactly what this guy did. This Diego Rivera painting has been in his family for around 80 years. It was purchased in the 1930's. That's really all he knew about it.

Once it was looked at by a professional, it was authenticated as a missing painting from one of the most important painters of the 20th century from his early years. The painting was done in 1904 when Rivera was just 18.

When she finally tells him how much it's worth, his jaw just about hits the floor, and rightfully so, as he had this thing hanging behind a door.