but the most important break comes from an unlikely source -- a piece of pizza. >> it just so happens that the fire never really hit that slice of pizza. that is what broke this case. >> for dna experts like lawrence kobilinsky, it's a pot of gold. >> you have a lot of cheek cells that tend to slough off into your saliva. there's a lot of dna in saliva. every time you bite into something, you are leaving small amounts of saliva behind. >> the pizza is taken to a forensic lab and immediately tested for dna. >> they compared that developed dna to a database, and out pops darrell wint. >> police have their suspect, a 34-year-old maryland man who worked for savopoulos ten years