Encounter , by m c escher , 1944 , tessellation , Op Art style
A black and white drawing of monkeys playing with humans.
A black and white drawing of monkeys and humans.  The monkeys are on the left side of the drawing and on the right side are all facing the same direction.  All the monkeys are black and the humans are white.  There is a white circle in the middle of all the monkeys.  Some of the monkeys have their hands up in the air and some of the humans have their arms outstretched.