During the last six years, Mark says he has sent more than $750,000 to help a woman he met on an online dating site get her inheritance out of Nigeria and to the United States. Mark says “Kelly Smith” promised to split the $3.5 million in cash and $3 million in jewelry and diamonds -- which she told him she put into two large metal boxes -- with him once the boxes arrived.

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Mark says he immediately thought it was a scam, until, he says, “Kelly” assured him it was a real partnership. So he says he began working with a shipping professional “Kelly” hired, Mr. Adeola, to transfer the name on the boxes and to pay the appropriate custom fees in an effort to help “Kelly” move the boxes.

It’s been six years, and Mark says he still has not received the boxes – and that Mr. Adeola continues to ask for more money.

Mark’s friend, Cyndy, contacted the Dr. Phil show worried that her friend, a doctor, was being scammed. But Mark says he knows for sure that “Kelly” is a real person.

In the video above, Dr. Phil reviews email exchanges between Mark and Mr. Adeola, and reveals new information to Mark. How does Mark respond? And on Tuesday’s episode, see the results of Dr. Phil’s international investigation to determine where the boxes are. Is Mark being scammed? Check here to see where you can watch.