"The Monster in the Box" (2009) is Ruth Rendell's twenty-second Inspector Wexford crime novel, but it's not her best. I don't think the very prolific Rendell is capable of writing a bad novel even if she tried, but this one is somewhat of a stretch and is a little far-fetched.Eric Targo has turned up back on Inspector's Wexford's turf. The book goes back to Wexford's early years when he was an unmarried rookie cop. He had been sent to a murder scene. A woman had been killed while her husband was out playing whist. It later turned out that the man was really having a liaison with his girlfriend. Outside the murder house young Wexford sees a short muscular man, Targo, out walking his dog. The man stares at him.From that moment on Wexford develops an obsession about the man and believes he was the woman's murderer. He has no evidence and can find no motive so he keeps the knowledge to himself for years. At times he is stalked by Targo who is an animal lover and has a strange birthmark on his neck which he always keeps covered by scarves. (We hear so much about the birthmark and the succession of scarves and his great love for animals that we get very tired of the repetition.) The book, in general, is repetitious. Another murder of a boy in a park takes place where Targo is tangentially involved, but again there's no motive and no evidence. There's a third murder that closely affects Wexford himself.For years Wexford keeps his obsession to himself about Targo, the monster, but finally he unburdens himself to his buddy, Inspector Mike Burden.Another plot is going on in the novel about a Muslim family, the Rahmans. Jenny Burden, Mike's wife, and detective sergeant Hannah Goldsmith have developed an obsession of their own. They believe the family's sixteen-year-old daughter is going to be forced to marry a man she does not know, and that later the family may engage in a honor killing if the daughter disobeys her parents. The lengths that Hannah goes to in getting involved in the girl's life, and the hounding of the family she engages in, are beyond belief. I can't recall a do-gooder overstepping the bounds of proper police conduct in the way she does.The two obsessions by Wexford and Hannah are so intense that they slowed down my reading. I had to take a break from their persistence. Wexford "wanted justice to be done and hated to see it fail...the wicked must not be allowed to flourish." Targo was "the homicidal dog walker" and "satanic."The book becomes tedious when people are often interviewed and reinterviewed by Wexford and Hannah.