>> couple theories, either douglas stewart enlisted the help of someone to come to michigan, abduct andsomeone completely unbeknownst to us involved in this with either a stranger abduction or someone that venus stewart was having a problem with type of thing. >> reporter: a woman goes out the front door in her pajamas and never seen again. someone would be rightfully fearful is there somebody crazy on the loose abducting people >> absolutely. >> reporter: and you're getting citizen calls, people saying i saw a funny looking guy at the lake the other day. >> yes. >> now police are looking to are this man, two witnesses spotted him at nearby adams lake the night before stewart disappeared. he was wet and approached the witnesses for a cigarette. >> i mean right now with the case we have so few clues to go on, we're not going to discount anything. >> the lead was strong enough that police conducted an all-out search of the lake using sonar equipment. >> reporter: police dredged that chilly lake after reports of the soaking wet man by the water's edge. they worked around the clock, but fou