>> my whole world just died right there. >> for months the murder stayed cold. >> didn't have witness, didn't have video, didn't have dna. we had everything going against us. >> we would go down and talk to the detective. we wouldn't let it go. >> then a break, another victim. >> he would duct tape me, duct tape my mouth. >> and she knew a secret. could she risk revealing it? >> something is going to happen tonight. >> a killer ready to run, face-to-face with the one person who might be able to stop him. >> he just reached over the glove compartment and he pulled out the gun, and i said, "please don't kill me." i wanted to get out of there alive. it was a monday morning in january 2007. 9:08 a.m. a young woman in san antonio,