"A&P: Overview" by Bruce KellnerReduced to a plot summary, John Updike's "A&P" is unpromising: a grocery store manager admonishes some girls for shopping in their bathing suits, and a young cashier quits his job because he has been attracted to one of them and wants to make an impression. Updike, however, has constructed a highly entertaining moral tale in "A&P," guaranteed to amuse but in the end to instruct with bittersweet wisdom that grows from the magic in the telling.