The engineer Daniel Rossignol travels with a research team to the other end of the galaxy to the planet Collinda, where he has accepted a job developing a fantastic machine.

The 'Elysium Project' aims to achieve the ultimate understanding of human identity by opening up the technical possibility of modifying reality by linking the probabilities in parallel universes.

The physical changes that can be programmed with this 'Nexus Machine' alone are fantastic and the Aeternitas company senses enormous business from wealthy customers who spend a lot of money on body shaping and reversing natural aging processes.

Driven by curiosity and a deep, personal longing, Daniel decides to try out the project's technology himself and let the Nexus Machine rejuvenate him, ending up in the body of a girl.

With the help of her friend Jean-Michel, she tries to find out the cause of the strange transformation, and they come across evidence of evil dealings.

But on Collinda, there is fierce resistance to the project. A rebellion against the conditions on the planet begins in the workers' settlement.

Eventually they manage to avert the impending danger by misusing the machine, and Daniel has to make a momentous decision.