detective paula zitzelberger is working in the sex crimes unit when the call comes in. >> she had beenbbed -- i think it was 17 or more times. her purse had been taken. but that was much more violence than needed to steal a woman's purse. >> the failure to sexually awe salt the woman leaves rhodes frustrated. but he isn't finished. before police can find him, rhodes is back on the prowl, searching for another victim. >> i was mad that i had to run. i was mad that i didn't succeed. there was a lot of anger there. and so i went right back into predator mode. >> you sound really mission-oriented to me, to complete a sexual assault. someone's going to get it. >> that was the mission that didn't get completed. >> not for long. >> i was on a mission and the mission wasn't complete. >> he liked that term. that he was a predator who was mission-oriented. it fit for him. he was in charge. he was the one out watching and following and the victims didn't know it. it was actually pretty chilling to watch that. when was the mission accomplished, in your mind? >> the point was to have sex. >> less t