This episode is a character study and an exploration of the meaning of life. It helps to suspend disbelief more than usual in this episode that raises more questions than answers. Virtually a one person performance by Larry Haines who does a remarkable job of portraying the changing emotions of a man held in sensory deprivation for several weeks as an unwilling participant in a social experiment. While most perish in the so-called Black Room, he survives with the help of a small mouse and a pin-prick of light.