When a murdered corpse of an unknown young noble is discovered, Fidelma of Cashel is brought in to investigate, in Peter Tremayne's The Seventh Trumpet
Ireland, AD 670. When the body of a murdered young noble is discovered not far from Cashel, the King calls upon his sister, Fidelma, and her companion Eadulf to investigate. Fidelma, in addition to being the sister of the king, is a dailaigh—an advocate of the Brehon Law Courts—and has a particular talent for resolving the thorniest of mysteries.
But this time, Fidelma and Eadulf have very little to work with—the only clue to the noble's identity is an emblem originating from the nearby kingdom of Laign. Could the murder be somehow related to the wave of violence erupting in the western lands of the kingdom? The turmoil there is being stirred up by an unknown fanatical figure who claims to have been summoned by "the seventh angel" to remove the "impure of faith." Fidelma and Eadulf, once again grappling with a tangled skein of murder and intrigue, must somehow learn what connects the dead noble, a murdered alcoholic priest, and an abbot who has turned his monastery into a military fortress. When it appears that things cannot get more complex, Fidelma herself is abducted, and Eadulf must rescue her before the mystery can be solved.
Set in 670 C.E., Tremayne's 20th full-length Sister Fidelma whodunit (after 2012's Behold a Pale Horse) is one of the weaker entries in an otherwise strong historical series. Fidelma, a law-court advocate, has given up her title of sister in the hope of securing a more senior position, which has gone to another. Now acting independently of "any Rule or religious authority," she finds herself in familiar territory after the discovery in a farmer's field of a well-dressed male corpse with multiple stab wounds. This murder proves to be the first of several the sleuth must try to solve. Unconvincing perils and an unremarkable solution matter less than Tremayne's inability to harness his talent to integrate the political intrigue and scheming of the time into the story in such a way as to make the stakes real to a modern reader.