MR. CAMPION'S ABDICATION

Margery Allingham's imperishable Albert Campion, now officially the last survivor of detection’s golden age, looks back from 1970 to the surprisingly multilayered intrigue surrounding the Duke of Windsor’s visit to a Suffolk archaeological dig shortly before he gave up the throne for the woman he loved.

Although it was never to rival Sutton Hoo, it seemed for a time that the Heronhoe boat excavation would put Sweethearting Mound on archaeologists’ maps, and in 1935, the future King Edward VIII came to Heronhoe with Wallis Simpson to take a look and be photographed. Their visit proved to be the highlight of the excavation, which turned up nothing much else. Even so, rumors of an Abdication Treasure the grateful Duke later sent the village persist. Now Italian TV documentary filmmaker Daniela Petraglia has swept in to re-create the visit; she’s attracted Mr. Campion as her producer and financial backer; and, in a perhaps related development, she’s cast his son and daughter-in-law, Rupert and Perdita, as the Duke and Mrs. Simpson. Admonished by an amusingly inappropriate emissary from the royal family to stay far away from any search for any possible treasure, Campion finds himself digging for something quite different: the truth about local journalist Samuel Salt’s failure to file any stories about the royal visit, a mystery that turns out to be linked to the unsolved murder of au pair Seraphina Vezzali on a London street soon after she was implicated in a series of home robberies in 1955—a death that’s long weighed on Mr. Campion’s conscience.

Ripley sets Allingham’s hero a more substantial mystery than in Mr. Campion’s Guilt (2016), and the evocations of everything from 1930s manners to an American teenager in 1970 are spot-on. Fans, however, are most likely to be drawn by the nonstop blather, which has a marvelous time-capsule freshness.