The famous poet Alexey Neredin went to the Cote d'Azur to improve his health, but the measured course of life in the sanatorium was interrupted by strange events. First, Neredin’s drafts disappeared, then the French officer’s letter disappeared, which he did not have time to read. And soon after this, a murder occurred in the sanatorium - a respectable elderly lady who loved to sit in a chair on the shore was pushed off a cliff. Everyone was at a loss, and only Amalia, an agent of the special service of the Russian emperor, understood: we were talking about a secret of national importance. And in order not to be discovered, someone is ready to commit any crime...