INTRIGUE IN ISTANBUL

Neubauer moves further away from the retro whodunits of her franchise's previous installments and closer to the hidden-treasure search beloved of interwar movie serials.

The long-awaited 1926 meeting between Redvers, a fiance with a mysterious past, and Jane Wunderly’s father is put on hold by the disappearance of Prof. Henry Wunderly, who’s left behind no forwarding address, a mountain of debt that’s coming due in a matter of weeks, and no message for his daughter. Has he been the victim of foul play? Probably not; instead, the best evidence is that he’s traveled to Turkey in quest of Suleiman the Magnificent’s heart, which was separated from the rest of the sultan’s body centuries ago and is buried in an undisclosed location. Jane, frantic to mortgage back her father’s home before hungry creditors seize it, takes off in hot pursuit along with Redvers, their inquiries complicated by the interference of Millie Stanley, Henry’s wealthy sister, and her fiance, Lord Edward Hughes, who’ve followed them to Istanbul; Maral Aslanyan, the restaurateur’s daughter who turns out to be Henry’s sweetheart; and singer Katerina Semenov, an exiled Russian aristocrat who’s one of a number of unexpected acquaintances Redvers has in Istanbul. Every time the lovers seem to be closing in on Henry, he turns out to have gone still further afield—though he does begin leaving behind notes asking Jane to quit looking for him and go home. The pace is leisurely, the structure episodic, the mystery slight. Fans of the series can trust their guesses about whether Jane catches up with her father and if Henry finds that noble heart.

Globe-trotting piffle.