is lou castro? >> i do. >> how does he handle them? >> he takes them and holds them between his palms and once the photos are out of the the envelope, he moves them around with his fingernails and does not pick up the photos by his fingers. >> he knew exactly what you were doing. >> he did. >> and he wasn't going to leave a print. >> no. >> what did that tell you about the guy that had become your nemesis? >> it raised my suspicion more. >> reporter: he needed help. he called clint snyder who had worked high profile cases like the wichita bt case serial killer. >> it was an amazing thing. in this business you don't believe in coincidences. >> reporter: ron enlisted another big gun to help id castro. fbi supervisory special agent john sullivan. >> we checked our fbi data bases and private data bases. we checked every lou castro we could find none matched the lou castro we had in wichita. >> how unusual is that that the fbi cannot come up with a name and an id on a guy? >> that is extremely unusual. e