abigail folger had gotten loose and was in a fight with patricia krenwinkel.confusion. people were running and screaming. i went over to the woman who was pregnant and she begged for mercy. and i told her i didn't have any and that she was going to die. then tex said kill her. and i said, i can't. and so he did. there was no remorse. >> there was no mercy. and when it was all over with, there was 102 stab wounds, 7 gunshot wounds. and when they left the residence they printed the word "pig" in sharon tate's blood on the front door. i mean, it's too horrible to even talk about. >> tex in his book said he got total instruction and he felt like he had charlie in his head the whole entire way like running a tape. nobody really knows for sure about charlie's motives and what he was thinking but charlie. i think he was getting more desperate to keep it all together and to keep control. >> many killers are pathological liars. they'll either tell you what you want to hear, they'll brag by admitting having done things you know they didn't or they play innocent. i think

>> manson and his followers, charles tex watson, who did most of the actual killing, patricia krenwinkel, shown here on the left, leslie van houten and susan atkins were all convicted and condemned to die in the gas chamber. their sentences, however, were later commuted to life when california temporarily dropped the death penalty in 1972. not long after, the fbi began researching serial killers and developed a profile on charles manson. one of the profilers who would study him was candice delong. what drew you to the study of manson? >> in training to become a profiler, we learned about all different kinds of criminal minds, and he was one of the many, many people that we studied. he was fascinating because a lot of people think charles manson is a killer. in fact, he directed others to kill. >> manson personally killed just one of the nine victims, the cowboy and aspiring actor, shorty shea. still, manson is thought by most people to be a serial killer. the whole image is one of intense evil, i guess. a frightening character who might slash out at any moment. people almost seem to be a