see it in your eye you remember it was me, okay? remember what, john? keep that in mind. it was me. tonia, you enjoy your time left on this earth. okay? because that s what it s gonna come down to. reporter: he was arrested for making threats against tonia in june 2001, was convicted of menacing and put on probation. he wasn t the man she thought he was. that s exactly right. there was another version of john. reporter: dennis luken was a police detective back then. he investigated the source of those drugs tonia found in the cedar box. he started at john s house. and found a gun. illegal, because john was on probation. so he was arrested again and sent to jail. when he went to montgomery county jail, i called a supervisor. i said, you ve got an individual there, john meehan, and he s going to try to con you out of drugs. he says, he already has. he claimed he fell out of the top bunk and he got pain medication. reporter: you re dealing with
reporter: luken discovered darker secrets as well. john supplied the opioids that killed his own addicted brother. he was alone with his sick father when the old man died rather suddenly. john wasn t charged in those cases, but there were others, said luken, and as the years went on, he developed a certain criminal specialty. he would go on dating websites and he would find women that usually had good financial backing. he always told people he was a doctor. reporter: he seemed like an ideal catch, i suppose. yes. reporter: for a lot of these women. he was a true con man. he d take their money and when they would find out about him john would threaten them, he would terrorize them. reporter: how bad was he? john was the most dangerous, treacherous, manipulative, deceitful criminal that i d investigated in 40 years of law enforcement. reporter: once terra learned about john s past, she was consumed with worry.
an incorrigible person here. yes, sir. you re dealing with an addict. a very smart, articulate addict. reporter: eventually, thanks to luken, john did jail time for stealing drugs in ohio and michigan. and tonia felt guilty, wondering if she d missed warning signs. wondered what else john might have hidden from her. never thought about the clue. way back at the beginning. on her wedding video. and the groomsmen who d had some drinks and have their arms around each other, and they re talking about how they met him. we re here to celebrate john. one of the groomsmen said john meehan s nickname is filthy john meehan. reporter: filthy john, over the years, became dirty john and the nickname stuck. reporter: you found out later on there was a story to that. yes. he was basically conning little old women out of money for jobs that he didn t do. and also that he had a way with the ladies.
medication. reporter: you re dealing with an incorrigible person here. yes, sir. you re dealing with an addict. a very smart, articulate addict. reporter: eventually, thanks to luken, john did jail time for stealing drugs in ohio and michigan. and tonia felt guilty. wondering if she d missed warning signs. wondered what else john might have hidden from her. never thought about the clue. way back at the beginning. on her wedding video. and the groomsmen who d had some drinks and have their arms around each other, and they re talking about how they met him. we re here to celebrate john. one of the groomsmen said john meehan s nickname is filthy john meehan. reporter: filthy john, over the years, became dirty john and the nickname stuck. reporter: you found out later on, there was a story to that. yes. he was basically conning little old women out of money for jobs that he didn t do. and also that he had a way with
the ladies. reporter: luken discovered darker secrets as well. john supplied the opioids that killed his own addicted brother. he was alone with his sick father when the old man died rather suddenly. john wasn t charged in those cases, but there were others, said luken, and as the years went on, he developed a certain criminal specialty. he would go on dating websites and he would find women that usually had good financial backing. he always told people he was a doctor. reporter: he seemed like an ideal catch, i suppose. yes. reporter: for a lot of these women. he was a true conman. he d take their money and when they would find out about him, john would threaten em, he would terrorize em. reporter: how bad was he? john was the most dangerous, treacherous, manipulative, deceitful, criminal that i d investigated in 40 years of law enforcement. reporter: once terra learned about john s past, she was