A point of interest is the fusion of the then-upcoming 1982 Soccer World Cup theme with the topic of Islamic terrorism, which was at that time still a "novelty".
A band of Oriental terrorists decide to execute a strike against the U.S.A. using a terrible weapon: A soccer ball housing bio-engineered bacteria which continuously produce a gas that turns any who inhale it into a donkey.
Due to a slight mishap during an attempted mid-air hijacking (since the plane passengers did not believe that the terrorist's hand grenade was real), the ball instead ends up near the Spanish coast, where it is unwittingly picked up by a number of boaters.
While Professor Bacterio is hardpressed to develop an effective antidote for this malady, the terrorist band repeatedly attacks the T.I.A.
As a final act, El Súper demands that Mortadelo and Filemón finally destroy the ball; but in order to do that, Mortadelo decants the gas into a scuba tank set which El Súper intends to take to a diving trip.