1) The snowman
"In Oslo, after the first snow of the season has fallen, a woman disappears, and a sinister snowman is left in her wake. As irascible detective Harry Hole realizes that this is only one of multiple disappearances, he begins to think a serial killer may be at work--and may be drawing in Hole personally and intentionally"--
Detective Harry Hole volume 9
Determined to prove the innocence of a young man he helped raise, disgraced former cop Harry Hole embarks on an increasingly dangerous investigation linked to Oslo's most virulent street drug.