Service in the navy has never been considered easy. Especially on submarines. And even more so in the years when the most terrible war in its history is blazing over the Motherland. Distant raids, attacks on enemy transports, battles with an invisible but deadly enemy - the heroes of V. Gusev’s novel “Sails on Fire” had to endure a lot. The story “Operational Raid” tells about the difficult service of military couriers and about the unexpected task that fell on share of Captain Sosnovsky's reconnaissance group.