. >> 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 they had made a mistake, and moved back home. >> gentlemen, change partners across from where you are. change partners and swing her. >> however, in this recent disappearance, neither teresa or her husband ron knew of melvin whereabouts. and the bank reported no activity on any of melvin's credit cards. >> he had a young son, he was early 20s, and this wasn't the kind of man that would run off and leave family obligations. >> which is why investigators began to suspect foul play. >>> 43-year-old melvin snyder, a gentleman farmer and factory worker, went missing. his family knew of no reason he would have left home. >> he would virtually have to live in