A New York artist believes he's "cracked the code" of Leonardo da Vinci's "Mona Lisa" painting.
Ron Piccirillo claims to have found a lion's head, an ape head and a buffalo head in the painting while turning it around.
In his blog he wrote that the painting is an optical illusion with one painting hidden within another.
UK Daily Mail reported that Piccirillo was surprised at his own findings and Googled it wondering how this has gone unnoticed for five hundred years.
The key to finding these illusions is to view them at an acute angle. If the viewer's eye is level with the painted horizon the viewer may not be able to see them.
But art connoisseurs are not buying his idea yet!