In J.D. Robb's ''Midnight in Death, '' Lieutenant Eve Dallas must postpone her first Christmas with her new husband, Roarke, to hunt for an escaped serial killer -- but she and Roarke still manage to find ways to celebrate...Susan Plunkett's ''Christmas Promises'' brings a woman and her ex-fiance together after four long years as they search for a missing child -- and make up for broken promises of Christmases past...In Dee Holmes's ''The Unexpected Gift, '' Sabrina McKay and her five-year-old son are coping with the first Christmas since her divorce when her son finds a ''body'' in the yard -- and unexpectedly they rediscover the true spirit of the holidays...In Claire Cross's ''A Berry Merry Christmas, '' a mysterious nanny has a special message to deliver to a young orphan and her uncle who long to feel the joy of Christmas in their hearts once again...