What is that awful green and purple gunk bubbling up in the normally blue waters of the Chesapeake Bay? Chadwick the Crab and his friends call it garplegrungen; people call it pollution. Whatever its name, Chadwick decides he has to get rid of it. Dr. Mallard (that old quack) tells him it's no use. But with the help of old and new friends, such as stately Baron von Heron and Belly Jeans, the shy flounder, Chadwick finds a way to save the Bay.