Plankton is, as his name suggests, a tiny deep green planktonic copepod who can fit in the palm of one’s hand. He has some stubby appendages and one yellow eye with a red pupil and a white (sometimes pink) highlight.
A running gag throughout the series is the fact that Plankton is smaller than the other regular characters. He is easily stepped on and sent flying back to the Chum Bucket with a mere flick of the finger. His small size has led him to develop a Napoleon complex, which is occasionally manifested as a desire for global domination.
