Six years ago, the wife of psychologist Alexei Tronov died under mysterious circumstances. To uncover the mystery of her death, he created a unique project that allows him to develop his innate detective abilities. And the project justified itself: its participants investigated the most complex cases in different countries. But the death of Stella Tronova remained unexplained year after year. Alexei had to come to terms, admit defeat and let go of the memory of the past. But as soon as he allowed himself to move on and start a relationship with another woman, a brutal attempt was made on her life. She only miraculously remained alive, and even then it is unclear for how long. The attacker's handwriting hints that this crime is connected with Stella's death. Everything indicates that someone is taking revenge on Tronov, but the psychologist cannot even guess for what. Now he needs to understand this as quickly as possible, gathering around him the best participants in the project, because any of them could become a victim of an unknown avenger.