Dennis investigates a vigilante incident; Megan loses her unerring objectivity while profiling a brain surgeon who can't save himself from brain cancer.

Dennis investigates the motives of a well-to-do housewife who returns home after vanishing without a trace five days earlier. Isobel profiles a profiler with a vicious speech impediment. A stubborn Kennedy refuses to beg Megan to come back to The Eleventh Hour.