In her former life as an Atlanta cop, Callahan Garrity trusted no one more than her partner, Bucky Deavers. Now, when her old friend asks her to go to the annual St. Paddy's Day bash, she can't say no. Looking for fun, Callahan gets the shock of her life instead. Bucky is shot in a liquor store on the way home.

Stunned but clear-headed, the tenacious PI turns on all her skills to find the culprit. What she discovers, though, are accusations that Bucky might be working both sides of the law as an accomplice In a string of robberies.

With her friend's life and reputation hanging in the balance, Callahan , her mom, Edna, and her feisty band of House Mouse employees kick the investigation into high gear, using their unorthodox methods to get answers. This time, it will take every skill they've got to pierce the veil of secrecy surrounding an Irish police organization and prove that the case is more than it seems.