Police say Peter Rule behaved like a gangster, and had a habit of threatening dangerous characters.
Homicide squad Det Sen-Sgt Ron Iddles said the fantasy probably cost the Meadow Heights dad his life.
"He talked the talk, but couldn't walk the walk," he said.
Mr Rule, 56, who doted on his 11-year old son, disappeared on the night of November 15, when he was said to be fearing for his life.
Weeks earlier, two of his cars were torched outside his home, the light bulb outside his front door stolen and the word "dog" painted across another of his cars.
Mr Rule had also successfully applied to be moved to another state house.
Det Sen-Sgt Iddles said: "Sadly, Peter had an attitude where he believed he was a bit of a gangster and often he would threaten people within the Broadmeadows area.
"He would make threats but never really had the intention to carry them through."
Det Sen-Sgt Iddles said his threats included burning down people's houses.
"He watched all the Underbelly series and for whatever reason he wanted to be a gangster. He spoke like a gangster, but he could never carry through what he actually said."
Mr Rule was last seen at about 8pm on Sunday, November 15, when he visited friends in Meadow Heights.
He got home about 8.30pm and spoke to his brother on the phone - the last time anyone heard from him.
Mr Rule's sister Stella McNaughton said: "He was all talk, he just didn't mean any of it. It just made him feel big. He loved his family a lot, and he adored his son."
Police hope to speak to a person who was seen in a small, black 4WD outside Mr Rule's home about an hour before he was last heard from.
Anyone with information can contact Crime Stoppers on 1800 333 000.
Missing Melbourne man Peter Rule feared murdered
- From: AAP
- December 06, 2009
Homicide detectives have taken over the investigation into the disappearance of Peter Rule, of Meadow Heights in Melbourne.
The 56-year-old was last seen about 8pm on November 15, when he visited friends in Meadow Heights. It is believed he arrived at his Mitchell Crescent home about 30 minutes later and spoke to his brother on the phone.
Mr Rule regularly spoke with his 11-year-old son on the phone but has not made contact with him since November 15.
"Further phone calls were made to Mr Rule's mobile phone later that day which went unanswered," a police spokeswoman said.
"Peter's car was found at his home address along with his dog that went with him everywhere."
He was reported missing on November 17.
Police are urging anyone with information about Mr Rule's disappearance to contact Crime Stoppers on 1800 333 000.
