International man of mystery Diabolik and his sensuous lover Eva Kant pull off heist after heist, all while European cops led by Inspector Ginko and envious mobsters led by Ralph Valmont are closing in on them.
A pair of Americans want to perform the greatest robbery: the treasure of San Gennaro, in Napoli.
At age 50, tax inspector Emerenziano decides to settle down and aims to the three Tettamanzi sisters, who, though not young or pretty by any means, have recently inherited a large amount of money.
