The protagonists of The Holy Four are Ondra and Vítek, electricians from the same company, who receive an offer for an exotic "summer job" on a Caribbean island where a hurricane had destroyed the electric lines. Ondra and Vítek are friends and neighbours from a duplex in which they and their families live in absolute harmony. Their wives, Dita and Marie, are friends and Ondra's teenage sons are dating Vítek's teenage daughters. It is simply an all-encompassing idyllic situation, except for one thing: boredom in the bedroom. So when fate throws them a gauntlet in the form of a foreign business trip, they pick up the gauntlet and their wives and head off to the Caribbean. And here, in this exotic paradise, they concoct a plan after which their sex lives will never be the same again. Or boring.