Shards of crystal dreams

Club "Crystal" was considered the best in the city. Matthew Abrams wanted to relax, drink and, if lucky, someone to meet. But the evening went wrong, and he was going home alone when it turned out that the "Crystal" a woman was murdered... I had to Abramov investigator to join the investigation.
A week later, in the same way killed a man, but not in the pretentious club, and in the Palace of engineering, which hosted the evening for those over thirty. These crimes are clearly related, although the victims existed in different worlds... Or not?