The 25-year-old left his Hastings home mid-afternoon on Saturday to buy fish and chips.
The plan was to return home for a late lunch with his partner, Clinton Hughes.
He never showed up.
Mr Dormer was driving his pride and joy, a white 1996Honda Accord which was found - a burned-out wreck - more than 300km away near the small eastern Bay of Plenty coastal town of Katikati on Saturday night.
However, there was no sign of Mr Dormer and he has not been seen since.
"The whole thing is a real mystery," Detective Sergeant Mike Foster of Hastings police said last night.
"There is no reason he would leave Hastings and there is no reason why he would set his car afire."
Mr Foster said police now had serious concerns for the man's safety.
He added there had been no fresh developments or leads by last night.
Adding to the mystery and fears about his disappearance, is the fact that he texted Mr Hughes at 3.35pm on Saturday with perhaps menacing information.
"I have this car following me. I'm just going to head to the fish and chip shop, stop and try to get down its rego [registration number]."
Two minutes later a second text message asked if his partner wanted smokes.
That was it.
Closed-circuit television cameras showed his car driving through Taupo at 5.30pm.
The vehicle is presumed to have crossed to Taupo via the Napier-Taupo Highway, State Highway 5.
Five hours later Mr Dormer's burned-out car was found on the side of the road in Katikati, 35km northwest of Tauranga.
The missing man's father, John Dormer, who lives in New Plymouth, told TV1 last night that his son visited him on Wednesday. "He was in great spirits."
Mr Hughes said the whole thing "Doesn't seem real. It's like a dream. It's something that doesn't happen to you".
Police were alerted after a highway patrol officer spotted the burned-out car at the side of the road in Katikati.
Hastings police have been checking Mr Dormer's bank and cellphone records to try to trace his movements.
"We'll review everything we have tomorrow [this] morning and take it from there," Mr Foster said last night.
