THE KILLER'S ART is fourth in the series of Gotland-set police procedurals by Mari Jungstedt featuring Inspector Knutas and his team. At the opening of the book, Visby gallery owner Egon Wallin is happily anticipating the sale of his gallery, and leaving his unsuspecting wife for a new life in Stockholm, with divorce papers drawn up and a moving van booked behind her back. He just has one last gallery show to open before he goes. After the opening, he sneaks out of his house, on his way to an assignation at a nearby hotel. But Wallin never arrives at the hotel; he is murdered, and his body displayed in gruesome fashion on the city walls.

Knutas and his team are in charge of the investigation, with assistance from the Stockholm squad, in the form of the engaging, chatty and ever-eating Inspector Kihlgard, Knutas's bete noire, but hugely popular with the other Gotland officers. Swedish TV reporter Johan and his pushy photographer, Pia, are sent over to Gotland to cover the story, a particularly convenient assignment for Johan, as it allows him to spend more time with his girlfriend Emma and their baby.

Despite assistance from Kihlgard progress of the investigation is slow, as the police follow up several inconclusive leads. Knutas has to consider whether Wallin's jilted wife is less innocent than she appears or whether there is any connection with the young Baltic artist Mattis Kalvalis whose gallery show Wallin had just opened, or even whether a cache of stolen paintings found in Wallins' basement motivated the murder. Knutas and Johan separately end up moving through the modern Swedish art world in the course of their research, coming into contact with various prominent art world figures in Stockholm's galleries and auction houses. A twentieth century painting, The Dying Dandy by Nils Dardel, crops up as a recurring motif in the investigation.