Detective Vellerman News Today

Letter. >> reporter: that is because melcher immediately recognized the photo. plus he said the original photograph was of two people. the missing man, he said, was his former roommate david strickland. if the snapshot was a surprise to melcher, the name david strickland was an even bigger one for detective vellerman. turns out he crossed paths with david strickland before. >> id interviewed david strickland in 2012 just days after the murder. >> remember that tip about a white car seen speeding...

That he had something to do with the murder. >> reporter: detective vellerman did the same, hoping this man would turn out to be the investigations third and final person of interest. coming up, a suspect. not acting at all like you might expect. >> he was enjoying this interview. >> maybe police have the wrong guy again. >> they would point at him in court and say thats the guy that did it. >> when "dateline" continues. all month long. and it comes in an easy-to-give tasty chew. and that make...