About the title
"There are secrets better left unknown." Five friends — Yura, Jules, Lika, Krest, and Kostya — notice that their classmates, seemingly unconnected to one another, keep disappearing one after another. Teachers explain it away as the sudden decision of their parents to move to another city. The parents pay no attention, assuming the child has simply fallen seriously ill and is in the local hospital. But these explanations don't seem plausible to our heroes. The five friends decide to launch their own investigation.
