A Trip to Merida is book three of the Grace trilogy, bringing any loose ends from Day 183 and Flight 885 to a close and an end to the Levindusky name. Set in 1977. Agent Brandy Bane, now with the DEA is assigned to work on a drug operation using a southwest Florida country club as a distribution center. FBI agent Bob Foreman has been assigned to work on a banking scam. Professor Harry Roth, a botanist, is drawn into the case as a consultant. He is eventually sent to the Yucatan on a mission to observe and report what he sees, using his studies as a cover. Dr. Sarah Roth provides technical support, identifying different mixtures of drugs with her brand new Mass Spectrometer. When the team discovers that there might be a DEA agent involved in the drug smuggling, the Secret Service provides a disinterested mediator to run the internal investigation.

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