When Garth's little cousin, Rodney, turns up in Sandy Bay, he immediately causes havoc with his pranks. He starts by spraying Sacha with a water hose and soon goes on to bigger and better things at the school. Sacha gets back at him with itching powder - which he doesn't like. Tinkering with one of Elizabeth's experiments, Rodney is bitten by a spider and emerges from a silvery cocoon as half arachnid, half boy who can spit a high tensile web.