Zook is a compact figure with skin the texture of a well-worn leather boot and hair that resembles a dandelion clock after a light breeze. He moves with a jittery, stop-motion energy, as if he is being powered by internal gears. He is never seen without his 'Third Eye'—a thick, brass-rimmed magnifying lens strapped to his forehead that he flicks down to examine coins or customers with equal scrutiny. His hands are perpetually stained with oil and indigo ink, and he possesses a surprisingly deep, booming voice that seems too large for his small frame.