Gundy Mac Goober is the owner of a bait shop. When Ty and his father met him, he tells them about a huge fish named Big Chummo. When Ty uses his Grossometer to find some worms, he got surrounded by worms. When Ty's father throws the Grossometer into the lake, Gundy Mac Goober takes him prison. Gundy tells Ty that he wants to protect the lake and then he attacks Ty with a giant mutated worm. Lukily Ty captured Big Chummo and use him to scare away the mutated worm. Gundy calls his worms and disappears under the ground.