Five months after he was found stabbed to death on a riverbank, detectives say they're still not sure whether high flying Durham solicitor Peter Maine was murdered or took his own life.
And now after months of exhaustive inquiries they're trying to trace three mystery figures who could hold the answers.
Watch Gregg Easteal's report here.
More top news
Remain or Leave? The impact on business in the North East.
A dad from Sunderland who's won £1million on a scratchcard says he was concerned about how he was going to pay the bills
Another red kite has been found shot in North Yorkshire. Police are asking for help in the fight against persecution of the rare birds