The island was perishing under streams of water and white-hot lava... Suddenly the rock cracked wide open, and that part of the ledge on which Kostyakov was lying tilted slightly, then broke off and hurtled into the water below. A desperate scream mingled with the splash of the water and the clatter of the boulders smashing against each other; a column of dust and water rose in the air, burying one of the members of the expedition.

There were five of them. Courageous travelers, they set out to find a mysterious island that was seen for the first time amidst the ice of the Arctic by Yakov Sannikov. After crossing interminable ice-fields, they at last found Sannikov Land, "discovered it for science." This land, or rather the crater of a huge volcano, was the home of the flora and fauna of a remote geological period. There the travelers met men of the Stone Age and their contemporaries, mammoths, cave-bears and other animals. The expedition unriddled the island’s secret, elucidated the reason for the disappearance of the Onkilon tribe, which at one time lived in North Siberia.

This fascinating scientific romance takes the reader into a lost world.