Something evil is lurking in the sewers, spreading, its hunger growing, waiting to be released into the world above...Martin is a plumber - usually a somewhat mundane profession. But not in this case. Sewage is flowing all over the city and toilets are overflowing. There must be an explanation. There must be something in the sewers blocking the pipes. Some people believe that the sewers are inhabited by giant alligators, clowns that eat children, or mutant ninja reptiles. But they are all wrong. What's actually lurking in the sewers is something much, much worse...