No Trace, by Barry Maitland

Another family-dysfuntion police procedural set in London, but I finished this one because the main characters in the series were doing their jobs.

The gist of the story is that the daughter of an experimental artist has disappeared in the middle of the night from the house where she lives with her father. He is an odd guy, and he immediately begins creating a new art series about her disappearance, encouraging the media circus to ramp up even more than it already is. The police are a bit at a loss, even though they manage to track down another missing girl and find the perpetrators of a serial kidnapping spree; unfortunately there is no trace of Tracy, and the one person who might have been able to tell them anything kills himself trying to evade capture.

Then neighbors of the family are murdered and things begin to spin out of control for the artist with no new clues to Tracy's disappearance. The whole thing looks like a personal vendetta when the artist is murdered, and then the puzzle pieces rearrange themselves and Brock and Kolla suddenly discover the pattern.

A missing child mystery with a surprisingly happy ending. It helps that most (not all, but most) of the people who are killed in the story are not very sympathetic, so it's rather a matter of just desserts when they go.