The Square (2008)

Lovers Ray and Carla plan to burn down her house at Christmas, to run off with her husband's drug money. Ray has a side scheme going too, taking kickbacks on the love hotel project whose construction he's managing. The suburban Aussie marrieds live across a river from each other, the much older, domesticated Ray in an upper middle-class neighborhood, Carla on the wrong side of the water. The cheaters will lure their families to the same Christmas picnic celebration, to provide alibis while still being able to sneak off and chat about the arson. Carla's tow-truck owner hubby, Smithy, is a fearsome tough to cross, so will the philanderers' holiday gifts come through, or explode in their lying faces?