An honest and humble gypsy lives in a poor neighborhood with his family until something unexpected changes his life forever.

The Ekipo Ja, a group of sane gypsies led by the gypsy Juan De Dios, is in possession, unknowingly, of a sacred seal able to make wishes to him who possesses it. And who wants to possess above all is the Marquesa, a wealthy stranger who does not hesitate to use cunning Italian art dealer persecuted by the police and associated with the Russian mafia, to remove the seal from Juan de Dios. But neither the Marquesa, neither the Italian nor the Russian, not even the Spanish Police, known the capacity Juan de Dios and his men to mess things up and, incidentally, become involved themselves.

A criminal produces an uncontrollable laughter to the population and Mortadelo and Filemón will have to stop him.