police found melvin's pickup truck about 60 miles away in reisterstown, maryland. it was in a grocery store parking lot. melvin's checkbook and .22 caliber rifle were still inside the truck. so the motive wasn't robbery. >> the truck was left windows partially down, keys in the ignition. i believe some of melvin's belongings were still located in the truck. other than that, truck was in fine condition except for marks in the back of the bed of the pickup truck. >> and the truck radio was tuned to a rock music station. >> melvin snyder never listened to rock music. >> melvin snyder was well-known in his small town. >> change partners. >> just a year earlier, melvin had an affair with a married woman, teresa harshman, who he knew from square dancing. melvin and teresa left their jobs and families behind, and fled to montana. melvin's wife joanne and teresa's husband ron took the opportunity to get better acquainted too. >> mr. harshman and mrs. snyder struck up a relationship and were intimate with one another. >> but after only three weeks, melvin and teresa decided