The Holy Quaternity.

Marital fidelity can wear you down, and Ondra and Vitek are certainly suffering from a case of serious fatigue. Working side by side and living next door to each other, it doesn't take long before these two long-married middle-aged pals start comparing sex notes, and it's plain to see their latest scores have fallen far below what they would have hoped. Luckily, a surprise holiday on a tropical island rekindles their interest in their wives - only they don't exacly lust after their designated partners. With no one to divert their attention, their roaming eyes inevitably settle on the wrong spouse, and pretty soon they've established their own little Holy Quaternity.