Spike Spiegel, a former member of the criminal Red Dragon Syndicate who left by faking his own death, is a bounty hunter aboard the spaceship Bebop. He's first introduced as the partner of Jet Black, the captain of the Bebop, and the two of them pursue criminals all across the solar system. During his travels on the Bebop, he is drawn back into a bitter feud with Vicious, a rival from the Syndicate who wants to kill him.

Spike is a nonchalant, unconcerned, and sometimes sarcastic character. He is usually seen passing the time by lounging, watching TV, or sleeping. In some rare occasions, he is seen practicing Jeet Kune Do, a martial art that he is very skilled in. Spike is almost always seen with a cigarette in his mouth - smoking despite the rain or "no smoking" signs around him.

Rather than following orders, Spike generally goes his own way which usually gets him in trouble. He often acts as if he's challenging death. He considers he's already died once and therefore doesn't show fear of the possibility of being killed. After the implant of his artificial eye, Spike says that his left eye (his real eye) sees the present while the right synthetic eye sees the past, making the past something he cannot get rid of or forget.