Wanted for multiple sex attacks against women in Northern California over three decades, this masked predator meticulously planned his assaults by studying the habits and routines of his female prey. The NorCal Rapist entered homes in advance of his attacks, memorizing floor plans and planning exits to avoid being seen. Then, armed with guns and knives, he attacked the women at night, mostly when they were asleep. But after 27 years on the loose, police suddenly closed in on the man they believe is the NorCal Rapist. This episode features victims, detectives, prosecutors, and criminal profilers, who detail the horror of the attacks, and the new forensic science that led to the suspect's capture.