When a rogue planet threatens a new Human colony, Valerian and Laureline are sent to investigate and discover a barren, rocky surface... and a whole world beneath it! The people who live inside Zahir have never seen the stars. Divided along gender lines, torn by a senseless and bloody war, they are unaware that their planet is hurtling towards disaster. To stop it, the two agents of Galaxity will have to infiltrate both sides and force a reconciliation....

The two Galaxity agents' investigation into the elemental forces appearing on Earth continues. While Laureline, dogged and efficient, follows a promising lead somewhere in outer space, Valerian is struggling to unravel the mysterious events plaguing our 20th century. Demonstrations of fantastic phenomena follow in quick succession, pushing poor Valerian to his limits. And matters will have to be settled simultaneously in New York and on an asteroid...