Based on Verne's book The Mysterious Island, five POWs escape from a camp in a balloon during the Civil War and crash-land on an uninhabited island in the Pacific. Trying to settle with their lives they find someone is helping them.

Engineer Stepan Mitin, having arrived in Kiev on business, accidentally gets to the performance "Ukrainian Ballet on Ice" and falls in love with the soloist Viktoriya Chaika. Delighted with the prima, Stepan doesn't notice that the draftsman Varya is working with him on the refrigerator project — the same girl to whom in the evenings he unsuccessfully tries to convey a bouquet of flowers with a note. The business trip ends — and Stepan, collecting in Primorsk, invites Varya to his plant. They agree to meet at the airport, but on the way, the ballet administrator intercepts the girl. Stepan flies away alone. One day, the Ukrainian Ballet on Ice comes to Primorsk. Stepan Mitin, the best refrigeration specialist, is asked to help create artificial ice. Stepan gladly accepts the offer and soon meets Viktoriya Chaika...

In 1905 Germany, Evgeny Narezhny, a talented bridge engineer and son of a Russian émigré, rejects lucrative offers to serve Russia. Arriving in St. Petersburg during the 1905 revolution, he focuses on science, believing it can solve global issues, unlike his Bolshevik wife, Elena Chernova. As a renowned scientist, Narezhny is repulsed by capitalism and is forced to reconsider his views on the revolutionaries’ struggle.

After a pacifist artwork incurs the displeasure of totalitarian state authorities, its creator is accused of the murder of a state official.