Twelve more gimmick-mysteries for the high-I.Q. Black Widowers to puzzle over after dinner at their monthly meetings--with, as usual, the plausible solutions always provided by waiter Henry. The clues/tricks this time include letter-codes, number-games, references to Cicero and Milton, multi-lingual wordplay (French, Russian, Greek), plus--in one particularly strained item--a combination of astronomy and an Edgar Allan Poe poem. There's one story for Gilbert & Sullivan fans only (revolving around that leap-year "paradox" in Pirates of Penzance). And Asimov offers two small variations on the formula: for the first time a woman(!) is allowed to be the guest who proposes the puzzle, to the horror of traditionalist Manny Rubin; and for the first time the guest is an uninvited intruder--who, as it happens, offers the volume's most see-through conundrum. (Readers will be way ahead of Henry.) With some amusing repartee, a few clever notions, and those half-endearing Asimov afterwords: more of the talky, easygoing same for those who relished Tales (1974), More Tales (1976), and the Casebook (1980) of the Black Widowers.