Greenback is smuggling sunlamps to the Eskimos to melt the polar icecaps flood the world. Unfortunately, Dangermouse and Penfold lose the Mark 3 and soon get lost on the North pole.
Crumbhorn has replaced Penfold with a mechanical transformer. Not wanting to be outdone by a villainous rival, Greenback disguises Stiletto as Penfold and orders him to replace the replacement.