Two married couples spice up their sex lives by forming a frisky foursome in “The Holy Quaternity,” a modestly appealing, barely convincing spouse-swap comedy that reps one of Czech helmer Jan Hrebejk’s slighter recent efforts. Game, flesh-baring performances from a likable cast keep this naughty-but-nice effort from overstaying its welcome at 79 minutes, even when its refreshingly nonjudgmental approach at times veers into bizarre wishful-thinking territory. Pic won’t stray too far beyond local boudoirs, but its gently bawdy appeal should seduce some viewers offshore.
Middle-aged marrieds Vitek (Jiri Langmajer) and Marie (Marie Prochazkova) live across from their close friends Ondra (Hynek Cermak) and Dita (Viktorie Cermakova). Ondra and Dita’s two adolescent sons are showing signs of interest in Vitek and Marie’s two daughters, an already odd premise that gets even weirder when the four parents decide to form a menage-a-quatre while on vacation together. Sun-dappled beaches and actors willing to expose their imperfect bodies onscreen make for pleasurable enough viewing, but even allowing for presumably ultra-permissive sexual mores, the overall vibe of casual, consequence-free tolerance feels both anti-dramatic and more than a little preposterous.