One day a former comrade of Watson, Peter Small, comes to an apartment on Baker Street. He brings with him a trunk full of jewels. Small is wounded and dies in the arms of the doctor. Watson refuses to believe that Small is a murderer and robber. Holmes is taken to help get to the truth. Moreover, the case is mysterious and dangerous. He assumes that a gang of cab-men is operating in the city. The bait should be a photograph, which depicts all of them - still young officers, graduates of a military school, along with one of their teachers. The next day, the beautiful Irene Adler appears in the Holmes apartment. After her visit, the photo disappears.
