In a cramped elevator, two identical siblings find themselves alone and bored. To pass the time, they start playing with balloons, their laughter echoing in the confined space. As they bounce the balloons off each other, they begin to feel a different kind of excitement. Their bodies press together, their hips grinding in rhythm. The balloons pop one by one, each explosion making them jump, their bodies rubbing together even more intensely. Their breaths grow ragged, their eyes locked as they lose themselves in the rhythm of their bodies.