Otto Penzler, editor of The Big Book of Christmas Mysteries, has a theory why so many crime fiction writers “have turned their pens and wicked thoughts to this time of year.”He believes it’s for the shock value.“Violence seems so out of character, so inappropriate, for this time of year that it takes on extra weight,” he notes in his Big Book, which turns Christmas Eve into Christmas Evil. “Think of how often terrible events have been recounted with the sad or angry exclamation, ‘And at Christmastime!’”Penzler is surely onto something, but his explanation doesn’t account for why readers are so enamored with holiday-themed mysteries. Or why a large percentage of the stories are warm, cozy, comical and relatively bloodless.So consider this additional theory.Do you remember shaking wrapped presents underneath the tree and trying to figure out what’s inside? Remember trying to crack the puzzler of where your parents stashed the gifts that come from Santa?Maybe this is why we’re predisposed to enjoying ’tis-the-season mysteries and thrillers. Because some of our earliest childhood memories connect Christmas with our own amateur detective work.And with that thought, we direct your attention to several of this year’s new Christmas mysteries.Spirit of Steamboat By Craig Johnson Viking, $20This novella, from the author of the Walt Longmire mystery novels, isn’t actually a mystery so much as an adventure/thriller.It involves a ghost from Longmire’s Christmas past and a tale from Christmas Eve 1988, during his first year as a Wyoming sheriff. Seems there was a terrible car crash with only one survivor, a child with burns so extensive that she must be rushed from Billings, Mont., to a pediatric intensive care unit in Denver.The problem: A record-breaking blizzard has made the roads impassable and the helicopter that completed the first leg of the trip no longer flyable. So Longmire must find another way to continue this rescue mission before the girl dies.The solution: Walt recruits a drunken ex-WWII pilot to fly a rattletrap B-25 bomber known as Steamboat the rest of the way.It won’t be easy. The crew must overcome not only bad weather conditions, but also a host of mechanical problems. (The scene in which Walt dangles precariously from the plane while trying to manually close the bomb bay doors is particularly thrilling.)There’s never any real doubt that Longmire and the gang will survive the ordeal. But it’s a white-knuckle journey just the same.The Big Book of Christmas Mysteries Edited by Otto Penzler Vintage/Black Lizard, $25This hefty anthology, released in trade paperback, contains 60 classic holiday-themed whodunits covering virtually all subgenres of mystery, from amateur detective to private eye to police procedural.Authors include many of the all-time greats: Agatha Christie (who has two tales in these pages, one featuring Hercule Poirot, the other offering Miss Marple), Ellery Queen, Arthur Conan Doyle (presenting the great Sherlock Holmes), Rex Stout (with Nero Wolfe) and John D. MacDonald.Two particular highlights are tales from the 1940s and ’50s that have O. Henry-style twists: Death on Christmas Eve by Stanley Ellin and The Chinese Apple by Joseph Shearing. That said, there’s also an early-1900s crime yarn written by O. Henry himself, A Chaparral Christmas Gift.Penzler, owner of The Mysterious Bookshop in New York City and editor of more than 50 anthologies, has a passion for this particular genre.Every year since 1993, he has commissioned a Christmas-themed short story from a top crime writer and printed 1,000 copies to give away to his bookshop customers. In short, he knows this turf.Silent Night By Robert B. Parker with Helen Brann Putnam, $24.95This short novel, featuring Parker’s best-known character, Boston P.I. Spenser, was unfinished at the time of the author’s death in January 2010. The book was subsequently completed by Brann, Parker’s longtime agent and friend.The story involves a young homeless client who brings a case to Spenser as Christmas draws near. It seems the lad’s mentor, who operates an unlicensed shelter for at-risk kids, is under pressure to shut down, which would put scores of young people back on the street.When Spenser and his buddy, Hawk, investigate, the trail leads to a dangerous drug kingpin.This book doesn’t rank among Parker’s best work, but it has its moments.Duck the Halls By Donna Andrews Minotaur, $24.99The author’s series of comedic mysteries, dating to 1999’s Murder With Peacocks, features amateur sleuth Meg Langslow and a recurring theme of birds, birds, birds.This one has Meg searching for holiday pranksters who leave skunks in the choir loft of one church and hundreds of ducks in another place of worship. Meg’s investigation takes a more serious turn, however, when an elderly vestryman turns up dead after a church fire.