Alan has been knocked over by a monorail; Herbert has fallen into the clutches of Opacus; Mary, Linda and Monty can’t stop arguing among themselves; and to cap it all, Foton has disappeared - brilliant as Gina is, even she cannot find a mathematical formula capable of solving this complex equation and coming up with a positive answer …. When Gina and Herbert try to resolve the problem of Herbert’s falsified grades while there is still a chance, they discover that the Invisible Man has fallen into the hands of the villains. With the help of Foton, the two of them work together to free the super-hero. But the cunning Opacus casts a long shadow. His plan to destroy the Invisible Man and all those who help him seems so well-conceived that it is unlikely to be thwarted by a couple of youngsters and a monkey ….