In January 1911, a bank was robbed in Novorossiysk. More than a dozen armed raiders burst inside, killed a policeman, stole a large sum of money and went into the mountains, firing back in pursuit. It was not possible to capture them. However, agents of the Yekaterinodar detective department found out that Circassian Kaitlesov was involved in the robbery. The arrested bandit gave very unusual testimony. The gang is led by a certain Varivoda. The ataman has a mysterious weapon in his hands - the “Kuban Fire”, which fires incendiary bombs over a long distance. With the help of this weapon, Varivoda is planning some kind of terrible terrorist attack in the capital of the Kuban region. Danger threatens the whole of Ekaterinodar...