radio the fbi was up to something in his town. >> and i thought, well, you know, maybe something is coming down, shall i run? but where would i have ran if they were after me. i just took a calculated guess that that was something else. >> reporter: then at mid-day, the killer went home for lunch. >> i drove home and just as soon as i got, started to turn down the road, i saw this whole line of police cars, i thought, oh, that's not good. it's just, they were right on me that quick. i thought maybe it was a traffic stop. as soon as one was behind me with red lights and sirens, i knew that was it. >> with that, dennis lind rader, the man believed to be btk was finally in custody after 31 years. >> i got to tell you, they told me to lay down. i sprawled out. they grabbed me with the handcuffs and stuck me in the car. mr. rader, do you know why you are going downtown?