During the week between Christmas and New Year's, the year-round population of Key West, Florida, faces a tsunami of tourists and snowbirds. It doesn't help that outrageously wealthy key-lime-pie aficionado David Sloan has persuaded the city to host his pie-baking contest. Every pie purveyor on the island is out to win the coveted Key Lime Key to the City, and Key Zest food-critic Hayley Snow is on the scene to report it.

Meanwhile, Hayley's home life is turning more tart than sweet. Hayley's new hubby, police-detective Nathan Bransford, announces that her intimidating mother-in-law is bearing down on the island for a surprise visit. Hayley offers to escort Nathan's crusty mom on the iconic Conch Train Tour of the island's holiday lights, but it becomes a recipe for disaster when they find a corpse among the glittering palm trees and fantastic flamingos. The victim—Au Citron Vert's controversial new pastry chef—was a frontrunner in Sloan's contest.

It's bad enough that Hayley's too-curious mother-in-law is cooking up trouble. Now, the murderer is out to take a slice out of Hayley. Can she handle the heat of a killer's kitchen?