Shelter by Kir Bulychev. Short summary

5 seconds

The fairy creatures ask Seva to find a Sanctuary for them in the Underworld. The boy discovers that a secret laboratory is ravaging the lakes to obtain an elixir of rejuvenation, and is pouring poisoned water underground.

1 minute

Teenager Seva Savin finds a frog with a crown on its head in the swamp. The toad transforms into a girl. The beauty asks the boy to help find shelter for the inhabitants of the fairy-tale world, who are in danger of dying on Earth.

Academician Sidorov of the Foundation for Development invents living water that restores youth. One gram of the elixir requires an entire lake of fresh water, which becomes poisonous after it is used. The president of the Foundation is going to get rich by secretly rejuvenating millionaires. To cover their tracks, the criminals drill a hole and drain the dead water from the lab underground.

Seva sneaks into the underground Sanctuary and sees that the poisonous water has killed all life in the troll city. The pipe comes from a former toy factory. Suddenly the underground rocks flatten a huge drill. The dead water spills back out and destroys the villains.