AviciousalligatornamedRamon,whowasflushedintothecitysewerasababy,survivestobecomea32-foot-longmenacewhodevoursanimalsandpeoplealike.Ramon'ssohugebecauseofthesteadydietofdeadpets-treatedwithgrowthhormones-thathe'sfedonfor12years.Nowthetremendousbruteisangryandlookingforrevenge.OnlydetectiveDavidMadisonknowsofRamon'sexistence,anditishistasktoprovetotherestofthecitythatatropicalbeastlivesintheirmidst.VeteranscreenwriterSayles'scriptfindstheperfectblendofcomedyandhorror,makingthisanentertainingrompthroughthesewersofChicago.