The Clock King, alias William Tockman, was a minor foe of Green Arrow whose crimes all have a clock or time-related theme. A former clock repairman, Tockman initially became the Clock King when he thought he only had six months to live, and needed money to help support his invalid sister (he figured that he wouldn't live long enough to go to prison anyway). However, after his first defeat by Green Arrow, Tockman learned that his medical report had been switched with a terminal patient, and that he was going to live. Unfortunately, he also learned that his sister died in a state nursing home.
Determined to gain revenge on his doctor and the Green Arrow, the Clock King escaped several more times. More recently, he has associated with other time-related villains, such as Chronos, the Time Commander, and the Calendar Man.