In the study with the wrench

"In the aftermath of Headmaster Boddy's murder, Blackbrook Academy has been thrown into complete disarray. Half of the student body hasn't bothered to return to campus--but those who have include Orchid, Vaughn, Scarlett, Peacock, Plum, and Mustard, now warily referred to by the other students as the Murder Crew. When another staff member is found dead and an anonymous threat begins to target the group, each of the teen's opportunistic reasons for sticking around come to light"--Provided by publisher.