On November 30 last year, Terje Johansen left his home south of Oslo.
A few days later, his car was found abandoned on Muskö outside Stockholm.
What he would do there no one seems to know.
The police have emptied two phones and a computer, but the only route Terje searched for is the one up to Northern Norway where he was supposed to look at houses.
Helped by Leif GW Persson
Lotta Thyni is now the local police in Botkyrka, but was previously an investigator in serious crimes and is still involved in the case.
She says that they even enlisted the help of criminologist Leif GW Persson.
- We felt that now we have done everything we can, says Lotta Thyni.
"Detailed search through everything"
Leif GW Persson believes that there are three possibilities when a person disappears like this: Sudden illness, an accident or suicide.
- In the case of the first two, they are usually found within a radius of a hundred meters and we have really thoroughly searched most of what goes on, and there is nothing to indicate suicide.
Hear what has happened to the investigation since last summer and what the next step is in the video.