The Interstellar Commonwealth, which united hundreds of planets inhabited by people, expanded and prospered for many years, but in an instant found itself on the verge of death. The Primes, aliens who arrived from Alpha Dyson, captured dozens of worlds using weapons of incredible power. However, this is not the only danger threatening humanity. The Star Wanderer, a mysterious alien whose existence almost no one believed for a long time, has been plotting for centuries and is now destroying the Commonwealth from within. Chief investigator Paula Mio is trying to figure out how he managed to remain undetected for so long, but just when the solution is close, the operation is disrupted due to sabotage. Now Paula faces a new task: to find out which of her colleagues became a traitor who decided to destroy the entire human race...