Jack is a recurring character in Shimizu's SF stories, a robot with a remarkably human-like psyche. Unlike many other robots of his time, he has the ability to consume food and even believed that he was once human. During a bounty-hunting mission on a foreign planet, Jack experiences a vivid flashback to a time when he and his partner were imprisoned and had to share meager rations. As the days went by, their food became more scarce, and his partner's health deteriorated, while Jack remained physically robust. Rescued months later, Jack discovers that he is not human, but still living, unlike his partner who tragically died of starvation.
