Wallace's Ping Pong O'Matic Automated Home Leisure System has hiccupped badly during field trials. When next door's pigeons then ruin Gromit's washing, man and dog face a hefty repair bill. Thus they enter an Invention Convention sponsored by the shadowy Acme Corporation.
So begins 'Anoraknophobia', which brings the pair face-to-eye patch with the sinister Herr Doktor Count Baron Napoleon von Strudel, inventor of the Acme Utility Anorak, and his hypnotic, spider-taming wife, Queenie.
The so-called von Strudels seem strangely familiar to Wallace, however, And man and dog soon find themselves entangled in Operation S.P.A.R.R.O.W. - a thoroughly evil plan to brainwash the cream of British brainpower - with serious implications for the future of table tennis and other indoor sports.