“What an adventure this will be!” - think Pashka Soldatkin and Sanya Chibisov, deciding to go down the river on a homemade rubber raft. On the very first day, their fragile ship is wrecked, their backpacks drown, and the travelers find themselves on a desert island. But is it really uninhabited? And how did the mysterious Black Forester, about whom the most ominous rumors circulate in the area, come upon him? And how did strange people in... a jeep end up in this wilderness? One thing is clear to the bosom friends: a new investigation awaits them...