Described in the media as "Sweden's Fritzl" – a reference to the Austrian father who held his daughter captive and raped her repeatedly over 24 years – the 38-year-old physician risks life in prison if found guilty of kidnapping and aggravated rape.
Wearing a blue fleece jacket and looking unfazed, he sat as a chilling account of the alleged crimes was presented to the Stockholm court.
His young victim was however visibly shaken, sobbing, and appeared with her hands covered by black gloves and her head hidden under a scarf. Not details about her age or identity have been disclosed.
"She's not well. It's very difficult for her to face him," her lawyer Jens Högström told the court.
The defence argued that the accused, whose name has not been published in Swedish media, was a "broken soul" and a lonely man with few friends.
"He desperately wanted a girlfriend," defence attorney Mari Schaub said, stressing that her client was remorseful.
He has admitted to keeping her against her will, but not to kidnapping or raping her.
"He was suffering from a psychological disorder," Schaub said.
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In earlier police interviews with officers the suspect said that "girlfriend might be the best term" for the woman, although he admitted she was "not a girlfriend in the ordinary sense, even I can understand that".
However the woman he locked up told police she feared she could be tortured or killed and her defence team believe that it was the man's plan to keep her locked up for years.
The rest of the trial was heard behind closed doors at the prosecution's request, and it proceeded to outline the defendant's planning and execution of the alleged crimes.
Prosecutor Peter Claeson speaking to media. Photo: Jonas Ekströmer/TT
According to the charge sheet, the man passed himself off as an American when he met the woman for the first time on September 10th at her Stockholm apartment, after having made initial contact online.
Two days later, he returned to her place with champagne, strawberries and fruit juice laced with sedatives. Once she was unconscious he is said to have raped her, then rolled her in a wheelchair to his car which had fake licence plates.
He then drove 550 kilometres from Stockholm to his country home near Kristianstad in southern Sweden.
He is then accused of having locked the woman into what the prosecution described as an above-ground "bunker" he had built in his yard, which resembled a garden shed from the outside. There he took blood and vaginal samples from his victim to make sure she was not carrying any sexually transmitted diseases.
Detectives first became aware of the man's unusual plot in September 2015, after he presented himself at a police station along with the woman, but he was not formally charged until earlier this month.
Meanwhile police have revealed that they are also continuing to investigate the possibility that the man was planning to abduct further victims.
The doctor is being tried by a judge; juries are not used in Sweden. The trial continues.