Summer on Cape Cod! While tourists pack the beaches and malls, Quansett locals meet for Tooner Sallid or Egz Bennie at Leo’s Back End. Inventor Pam Nash bursts into this sanctuary like an IED. Can her reclusive old friend and fellow genius, the artist-author Edgar Rowdey, save her new Zappa? This revolutionary “Taser for pacifists” is set to debut at a waterfront lawn party on Saturday. But Pam’s daughter Ashley, scared out of Las Vegas by death threats, is flying home to turn 21 with her family. How do you combine a VIP weapon launch with a birthday party? Leo’s sous-chefs, ex-Fix-It Chick Lydia Vivaldi and Wampanoag Mudge Miles, agree to cater. But when Lydia finds a dead party-goer floating beside the dock, Edgar is forced to change from guest into sleuth. Was the victim murdered? If so, why? And how? While the police investigation trundles along its slow methodical path, the body count threatens to skyrocket. As Edgar reluctantly starts nosing around, he learns there’s already been another death. Recognizing the murderous shell game they’re up against, he and Lydia race to piece together random but crucial facts from everyone in Quansett, before the killer destroys the Nashes and Zappa.