Mona Lisa

Shrouded in mystery
The Louvre remained reticent about whether it had lost the Mona Lisa at all. The only documents about the painting during World War II attest to its having been crated up on August 27, 1939, and sent with other French national treasures to a series of five chateaux, for safe-keeping—theoretically just ahead of the advance of the Nazis south through France, though the invaders quickly overtook the entire country.
Can you spot the original? The portrait on the left is Leonardo da Vinci's original, the painting on the right is the 16th century copy.