Junior's grandfather comes to visit and tells Junior that it is best not to be greedy for it may get him in trouble. Junior finds a rainbow and wants the treasure at the end of it. Bigweed has his eye on the rainbow as well and gets into it with Junior over the loot. Junior sees other Snorks who are after the treasure, and he and Bigweed work together and agree to split the treasure (each plotting to take it all for himself secretly). They reach the treasure, and get sucked into an underground world where they meet an octopus named Greedypuss. It turns out that he put up the rainbow in order to attract greedy treasure seekers because greed makes him stronger and stronger. They both get enough treasure to last them a lifetime, but when they get to leave, Greedypuss does not let them go. Junior comes up with a plan to get out, and so does Bigweed. They work together again to obliterate Greedypuss when they realize that he swells up everytime someone gets greedy. They make him grow smalle