With a trembling hand, Dr. Luck handed nurse Nina a cardboard that read "100 carats" in large letters. Several subjects were depicted. There was a cross. The patient, after giving the cardboard to the nurse, died so quickly that he did not have time to explain his crossword puzzle. The nurse realized: "100 carats" is something. But what? She remembered that there was a certain diamond lady Agnes Markina. And she decided that she could give her a cardboard, and let her suffer with her.