Soviet Union, late ‘70s. During his lecture at Knowledge Society in Kyiv an elderly professor talks about strange creatures even described by Marco Polo and who also lived on the territory of the ancient Russia…Soviet Carpathians. Small isolated farmstead, lost in the woods near a mountain lake Synevir. One morning, a brother and sister Sashko and Ivanka are secretly escaping their home to go fishing on Synevir. At first the kids are busy fishing and arguing who will take more fish. Suddenly they hear ‘haaloo’ in the woods. Ivanka and Sashko decide that some tourists got lost and need help, but they were mistaken…