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5/5 The detective puts herself in personal jeopardy to catch the murderer.
4/5 A fresh cryptogram alarms the detective. Has the murderer changed their system?
3/5 A mathematician helps the detective determine the killer's victim selection system.
2/5 The cryptogram clues leave the detective baffled over the serial killer's motives.
1/5 A woman is missing, but the detective's only clue is a series of jumbled letters.