The WITSEC house remodel is done, but before Minnie and Seamus can open the house as a safe haven for witnesses in hiding, Minnie discovers a tunnel beneath the kitchen that has been the site of a recent brutal murder. When an arrest is made, Minnie has serious doubts about the suspect and calls Martin and her brother to help uncover the real murderer. At first, they don't investigate the construction crew that did the remodel or the law enforcement agents who have overseen the work because they've already been vetted by the FBI, WITSEC, and the US Marshals. But when a second murder occurs, they give everyone a closer look. By the time Martin arrives in Atlanta to help, Minnie has already scheduled a dinner date with one of his least favorite people. She and the man share a love of baseball, which makes him even more attractive in her eyes. Martin has a hard time hiding his irritation, but Minnie's not willing to back down-she's determined to prove Martin wrong about this man, even though she and the man she's dating completely disagree on one very important point-who is and who isn't the murderer.