Mr Parker Pyne spent thirty-five years compiling statistics in a government office before retiring to apply that experience in an unexpected way. He places an advertisement in the personal column of The Times: "Are you happy? If not, consult Mr Parker Pyne." Treating misery as a problem with predictable causes, he holds that nearly all unhappiness can be sorted into a handful of types, each one logically solvable for a fee. The early cases unfold in England, where clients bring him a dull marriage, a discontented spirit, or a vanished thrill, and Pyne sets matters right by quietly engineering little dramas, often with help from his staff. The second half of this collection moves abroad, following Pyne as a fellow traveller in Baghdad, Shiraz, Delphi, on the Nile, and at sea, where the puzzles turn toward conventional crime: theft, kidnapping, and murder among holidaymakers. Across both modes the stories stay brisk and self-contained, balancing wit with neat deduction. The cast around Pyne is notable for Christie readers: his secretary Miss Felicity Lemon and one of his writers, the novelist Mrs Ariadne Oliver, both appear here before becoming fixtures of the Poirot books, alongside the elegant agents Claude Luttrell and Madeleine de Sara. The result is a lighter, more playful corner of Christie's work, where the detective begins as a curer of the heart before settling into the role of an observant traveller who cannot resist a mystery.