The Last Devil to Die by Richard Osman

When Kuldesh Sharma, an old friend of Elizabeth's husband, Stephen, is killed, the Thursday Murder Club finds themselves investigating another murder. Joyce, Ron, Ibrahim, and Elizabeth want to uncover Kuldesh's killer-- but why was Kuldesh in possession of heroin that has now gone missing? As the bodies and suspects pile up, the quartet have more questions than answers. Will they again prove that they are better than the police in solving crimes? This fourth book in the series has lots of delightful scenes with a serious undertone throughout the book. The puzzle itself, however, was a bit drawn out.