A pair of red-trimmed off-white butterflies are found living in the land of Siberia. The insects are native to Japan, so scientists find it strange that they would be discovered so far away from their homeland. In response, an expedition is dispatched to their habitat, located along the Kitami River, to discover why the insects might be living in Siberia. Two members of the scientific community helm the expedition, but are mysteriously crushed by something that the police can only describe as "powerful." The nearby villagers of the Kitami River insist that the deaths were a result of the wraith of their mountain god: Varan.