After several painful days of absurdly cold weather, Blomkvist is happy to see the temperature rise to the mid-teens (Fahrenheit). The weather's turn also brings him in contact with more of the Vangers he has heard so much about. First, Blomkvist has an enjoyable dinner with Martin and Martin's girlfriend, Eva. Several times throughout the dinner, Blomkvist wants to ask Martin about Harriet, but as Martin never mentions his sister, Blomkvist assumes the topic isn't on Martin's list of favorite discussion items.
Blomkvist's next encounter is with Cecilia Vanger, Harald Vanger's daughter. She stops by unannounced one afternoon and after a few moments of small talk, quickly gets to her point: Cecilia wants to know if Blomkvist's real job is to investigate Harriet's disappearance. Skillfully dodging the question, Blomkvist is able to get Cecilia to warm up to him. At the end of their conversation, Cecilia suggests Harriet's disappearance was simply the result of a freak accident.
After his Vanger family sightings, Blomkvist arranges to meet Detective Morell at his home on Lake Siljan. Blomkvist asks Morell if there's anything he left out of the police reports that could be of use to Blomkvist in his investigation. Morell says he has been haunted by Harriet's case as much as Vanger has and that he's left no stone unturned. Morell thinks one of the biggest clues is Harriet's desire to speak with Henrik Vanger before the accident distracted everyone; the detective figures she may have learned something another family member didn't want her to know. Morell adds that all investigators have one unsolved and haunting case — Harriet is his.
Every afternoon, Vanger and Blomkvist meet and discuss various aspects of Blomkvist's investigation. Blomkvist finds himself growing more and more fascinated with the assignment, partially because he wants to avoid his own troubles. Eventually, his old life catches up with him, as Berger returns Blomkvist's many phone messages at the end of January. She tells him the magazine is at risk of going under and that she wants to see him. Berger comes up for a visit and Blomkvist fills her in on the Vanger assignment.
The chapter ends with a return to Salander, who is about to have her third meeting with her new guardian, Bjurman. During the meeting, Bjurman asks her explicit questions about her sex life, which she at first refuses to answer. Then, realizing her refusal could lead to greater troubles down the road, Salander begins to respond curtly. However, Bjurman continues to push her to disclose more and more intimate information. Salander leaves the meeting, realizing her relationship with Bjurman will not improve.
Throughout Chapter 10, Stieg Larsson builds complexity into his narrative by using the motif of hot versus cold and exposing and deepening Salander's character.
The chapter begins with a report of the fiercely cold weather in Hedestad and on Hedeby Island. The chill ebbs as the month of January continues. Throughout the novel, Larsson comments on Blomkvist's experience of the cold in Hedestad, beginning with his first visit to see Henrik Vanger, and continuing with his efforts to combat the cold by buying extra clothes and wrapping up in blankets after he moves there. Through this tug of war between cold and heat, Larsson is able to mirror Blomkvist's struggle for truth, the cold representing deception, his struggle to maintain warmth representing his attempts to unmask the truth. Blomkvist makes headway in Chapter 10: With the temperature rising, his relationships with those around him begin to thaw and take shape as he meets with various Vangers and Detective Morell to discuss the investigation. This motif develops throughout the novel, with cold and heat becoming associated with various characters. For instance, Harald already is associated with cold, because his house is always packed in snow as he refuses to let anyone shovel his walkway for him.
Finally, Salander's exchange with Bjurman not only foreshadows problems in her association with him, but also draws a parallel between her relationship with him and her altercation with a man groping her at a train station when she was 17. First, the fact that Bjurman quizzes her on her sexuality, especially when they're alone in his office after his secretary has left, suggests his motives are not innocent. Secondly, Salander's discomfort with the discussion and her decision to create a make-believe lover based on what she thinks Bjurman wants to hear indicates that she continues to fiercely defend her privacy. Salander also doesn't want to address the topic of her sexuality, either outwardly or within her own thoughts — perhaps because of her past incident, or perhaps for reasons yet to be revealed.