Detectives discovered a plot to kill his mother, father and 10-year-old sister in Sochi, Russia.
He detailed how and where his family should be murdered, drawing up a floor plan that showed where the cameras were placed and how to avoid guard dogs.
But the hit man he was giving all the details to and agreed a fee with was actually an undercover police officer.
His parents were said to be devastated by their son’s plan but took part in a police mock-up, using fake blood with blood coming out of “fatal” knife wounds.
The “assassin” arranged a meeting in a Mercedes and showed the photographs of his “slain parents” to the man. No pictures were released of the man’s sister and it is unclear if she took part in the police set-up.
After seeing the pictures, the man expressed “delight” and agreed to pay the promised £38,000 fee to the man he believed was a contract killer as soon as he had collected his inheritance.
Instead, the son – who has not been named – was immediately detained by armed police as a police video shows. He immediately confessed, according to police in Krasnodar region, who revealed that the evil son had twice plotted to kill them previously.
“Before looking for a killer, he tried to get rid of his relatives twice. He checked the internet to find out how to carry out the murders.
“The criminal wanted to put pills in the kettle to poison his parents, but his father found out something was wrong.
“Then the son planned to break a thermometer in his parents’ car so that they were poisoned with mercury vapours. But he got cold feet.”
During interrogation, the young man said: “I had been planning it for several months. I’m so done with them, they didn’t understand me, so I found a contract killer.”
His parents ‘cannot believe he could do this’, said police.
His father runs a major education institution in Sochi. The family have a large house and car as well as savings which would have gone to their son.
The man faces 15 years in jail if convicted of preparing the contract killings of his family.