A group of sewer workers become trapped in the system after a pipe bursts and closes them off from the entrance. The film begins in their offices and involves the whole staff of five. A child has entered the sewer system through a storm drain, and the sewer workers are tasked with finding the child before a rain is expected to occur later that evening. After suiting up, the workers realize that the child must be found within the hour, as rains have begun to fall. They must quickly work against the clock to rescue the child or even themselves.