that's where i got the print. >> but there was a problem. investigators couldn't see the print clearly, so they sent it to the fbi in washington, d.c. fbi image analyst richard vorder-brugge scanned the image and examined it digitally on a computer. he immediately saw the problem. the texture of the skin on the victim's leg obscured the fingerprint. >> there were two different patterns we're dealing with here. you are dealing with the pattern of the fingerprint, which is a specific type of pattern, and then we have this texture of the skin that is distinct from the fingerprint. >> with the aid of the computer, vorder brugge first had to identify the victim's skin pattern, then have the computer remove as much of that as possible. >> it's a trial-and-error technique. it's not unlike an archaeologist