Fate itself presented Ekaterina Petrovskaya and Hector Borshchov with an unforgettable wedding gift — the investigation of the case of the missing expedition… In 1931, Professor Veliantov and his friends discovered a grandiose find in the Tien Shan Mountains. Realizing the importance of the discovery for world science and the danger facing the expedition in those wild places at that time, the professor sends fragmentary notes, photographs and ... the most important "proof" to various recipients. What the scientist foresaw happened — the expedition disappeared into the mountains without a trace.Almost a hundred years later, the mysterious death of Elena Krasnova, a researcher at the Zoological Museum, and two other people stirred up information about the missing expedition. These murders are being investigated by Colonel Gushchin, Katya Petrovskaya and Hector Borshchov. And in order to find the culprit and discover that priceless treasure, hidden from people for almost a century, they need to go to Tien Shan…Tatyana Stepanova is a police lieutenant colonel, a former employee of the Press Center of the Moscow Region Police Department and an investigator, which is why her action—packed novels so plausibly and in detail describe the investigation of criminal mysteries. Tatiana works daily with information about real crimes, and her detective stories are as reliable as possible.