The holiday of Goomer is upon Melmac, and Larson Petty is intent on getting his gift of foam - but while trying to kidnap the real Goomer, he ends up capturing Bob Shumway in a Goomer suit. Gordon and his sister Augie must then journey to find the real Goomer and rescue their dad.

Gordon invents an all-purpose object named the "Shumwidget", but Augie and her scout troupe end up with the bragging rights.