Тайна старинной миниатюры

Dvenadt͡satiletniĭ Kosti͡a stanovitsi͡a nevolʹnym svidetelem strashnogo prestuplenii͡a! Na ego soseda, Petra Ilʹicha, kto-to napal v podʺezde. Ranenyĭ v grudʹ Petr Ilʹich uspevaet peredatʹ Koste starinnui͡u miniati͡uru i prosit ne govoritʹ o neĭ nikomu… No malo kto znaet, chto Kosti͡a - otlichnyĭ syshchik! I, konechno, on ne mozhet ostatʹsi͡a ravnodushnym k ėtomu prestuplenii͡u. Vmeste so svoeĭ sestroĭ Masheĭ on nachinaet opasnoe rassledovanie, t͡selʹ kotorogo: naĭti prestupnika i raskrytʹ taĭnu starinnoĭ miniati͡ury!

Twelve-year-old Kostya becomes an unwitting witness to a terrible crime! His neighbor, Pyotr Ilyich, was attacked by someone in the entrance. Wounded in the chest, Pyotr Ilyich manages to hand Kostya an ancient miniature and asks him not to tell anyone about it… But few people know that Kostya is an excellent detective! And, of course, he cannot remain indifferent to this crime. Together with his sister Masha, he begins a dangerous investigation, the purpose of which is to find the criminal and uncover the mystery of the ancient miniature!