Magdalena, the rich and decadent tenant of a beautiful house, organizes the birthday party of her favorite, Eric. She invites his young friends to the party but a mix of childish naivety and sexual energy pervades the atmosphere. The celebration turns out to be a vortex of folly driving the participants to the point of non-return during a biblical reenactment.
Loosely inspired by "The Antique Wardrobe" by French author Georges Bataille and his theory of the relationship between love and death, Happy Birthday is nothing more than the representation of a dance of death.