Seventh in the series--and the first hardcover-- featuring ex- FBI agent Gregor Demarkian (``the Armenian-American Hercule Poirot''), who's solved crimes at Christmas, Thanksgiving, Easter, etc., and is now back to Yuletide, this time in picturesque Bethlehem, Vermont, site of a two-week-long Christmas pageant that nasty Tisha Verek had filed court papers to stop. Then she's stopped by two rifle shots, as are an elderly knitter; Tisha's husband's mistress; and the Episcopalian minister. Whodunit? Many local types are offered up as suspects, but then Gregor zeroes in on Tisha's book proposal--about children who've murdered, and are still living. Could one of the townspeople have a secret past? And have killed and killed again to conceal it? With an assist and comfort from girl-chum Bennis and friend Father Tibor, Gregor pinpoints the murderer and brings peace back to Bethlehem. On-target snipes at New England tourists, back-to-the-land yuppies, and small-town gossips. And the author can be charming- -albeit long-winded.