Inspired by Stanislav Lem's short stories about the spaceman ljon Tichy, X tells a tale of space travel adventure. A spaceman looses his identity when an inexplicable space machine produces countless copies of him and his spaceship. In his fight to eradicate these counterfeits, his own authenticity comes into question... The Loss of uniqueness of identity and the problems of identity in general are the subjects of the film. They are treated in the humorous narrative style of the animated film. The story itself is based on several ideas of which the viewer realizes only at the end how they are connected.