A community of land hermit crabs underneath a New Jersey beach boardwalk often play host to a community of sea hermit crabs that come to the land for vacation and both species of crabs can't stand each other. Armen, a timid land crab, is reluctant to go out and socialize due to how his parents died in a storm when he was a child and his rotting shell, inhabited by a fun-loving organism named Anemone, is the only reminder of them. However, three muscular crabs and Armen's friends, Bobby, Manny and Jimmy, drag him to a club owned by his uncle Bruno. The crabs get into a fight with an arrogant sea crab named Mako when Armen inadvertently bumps into Ramona, a tourist sea crab he fell in love with earlier. The land crabs get evicted as a result and Armen frustratedly takes his leave. As he is sulking by the seashore, Mako and his goons come to hassle him and steal his shell. Ramona intervenes, but she and Armen get swept away in a high tide that ruins the land crab civilization.