Un, dos, tres, al escondite inglés (1970)

A band of young musicians will do the impossible to boycott a song they didn't like at all, and that's supposed to represent Spain in a famous musical contest. An unusual film by the odd Zulueta in which, after the success of Spanish singer Massiel in Eurovision contest, this kind of contests are parodied with an insane story shot without a script and with the performance of several top music bands of that time.