After a local drug dealer dumps his stash into the ocean surf, a family's 4th of July beach weekend is ruined when a lurking species of prehistoric crustaceans (locally known as horseshoe crabs) react badly to a methamphetamine concoction and wreak terror, feasting on beach goers across the crowded boardwalk.

 

      A local scientist and aquatic animal activist  who has devoted his life to the mysterious life form, joins the family in a race for their lives along with the help from other local talent including a lifeguard, hot dog seller, a carney and a fire breather from the local side show.

 

      After the rag tag alliance fight their way through the sun kissed feeding frenzy and take refuge for the night in the side show theatre, they emerge to a horrific nightmare where the crabs have developed a parasitic relationship with the remaining beach goers and have ultimately taken over the shoreline.

 

     Using whatever skills and means at their disposal, the surviving summer dream team fight for their lives and discover the secret to sending the Meth Crabs back to sea once and for all.