Zach Flynn is a private investigator who must find out if Sean O'Riley's sudden illness was deliberate and what exactly happened to his charter boat business partner, who mysteriously disappeared with his passenger from a charter, the day Sean left for Ireland.
Sean, in his seventies, goes to Ireland with his trophy wife, who is hated by his daughter as they are close in age, and when getting off the plane becomes violently ill and is hospitalized. His daughter Kat, calls Flynn to ask him to go to Ireland as she is sure the wife was responsible for his illness. The day before, Sean's partner Eddie disappeared from his charter with his passenger and the boat was found floating near an island off the Rhode Island coast with no signs of anything amiss.
Flynn is not convinced that Sean's illness is nefarious, but agrees to go anyway and sets up an undercover to watch over Flynn until he gets there. When he does, he meets Caer, the Irish nurse in charge of O'Riley's case. The trophy wife behaves very oddly at the hospital, and even tries to have sex with her husband, even though she has been told he must remain calm due to the heart problems brought on by the mysterious illness. Caer and Flynn begin wondering what her intent was. When Sean is able to travel, they take him back to the states, with Caer in tow as his private duty nurse, or is that all she is. She is assigned the case by her boss, but he doesn't seem to be involved with the hospital.
They arrive at the home on the bluff and we are introduced to the rest of the family, including Bridey, Kat's grandmother who hails from Ireland, which causes the story to be peppered with Irish stories about leprechauns, fairies and eventually, banshees, once the crows show up in droves. We also meet the husband and wife team that run the charter boat office.
Flynn in the meantime, starts investigating Eddie's disappearance. He talks to the police who don't have a clue. He looks into Eddie's computer and office and finds that Eddie was still investigating a lost treasure from the Revolutionary War, that he and Sean had been looking for for years. He checks the boat and agrees there is nothing untoward there, but then he finds out that Caer, who he begins to fall for, is also investigating, and when he questions her about it, she says she is a banshee, though that makes him more suspicious.
Then they find Eddie's body, washed up on shore.
He then discovers that Eddie had sent a present to Sean for Christmas, which should be arriving soon, and he thinks that may have something to do with his disappearance. Caer finds a bunch of dumb poems in Eddie's office and she and Sean think it may have to do with the treasure. So they go out to the island where the boat was found and find a likely place, based on the treasures. He also finds evidence of talc, which matches the talc he found on the boat - the only clue they have. He convinces the town policeman to guard the desolate island run by the park district, and while there, the policeman is murdered.
He gets a break when he stops at a small shop on the wharf, and a young man working there mentions having seen the passenger Eddie took out that day. He gets the description, but then after a party held in town, the boy is walking home and someone steps out of the shadows, but Caer, who had a sense something would happen, goes out to help the boy and is stabbed instead. Flynn and Caer had begun a romantic relationship, and he is devastated by the stabbing, but she assures him she doesn't need to go to the hospital. He doesn't listen, and by the time they get there, the would is almost healed.
When they get back to the house, Bridey is dying and she somehow knows that's the reason Caer is really there. Flynn, meanwhile, is helping the police investigate the murdered officer and the package arrives for Sean. The package proves what Flynn suspected, the treasure caused the disappearance and deaths. He then shifts his investigation and Caer helps him look at the problem from a different angle. It is almost time for her to go back to Ireland, when, on Christmas, Flynn puts the pieces together, determines who the murderers are and who Caer really is and it is a surprise to all involved.
Best part of story, including ending:
The mystery was a mystery to the end, the characters were likeable and believable, the investigation took a reasonable path and the Irish stories were great.
Best scene in story:
My favorite scene was when Bridey was dying. Caer was with her and then Bridey realized all of the Irish stories were true and she figured out who Caer rally was, and she was no longer afraid to die.
Opinion about the main character:
Flynn was good because he was suspicious enough, though not so suspicious that he let it take over him, and he was also willing to listen to anyone's theory and reject or pursue it.