'Unholy Night' by Seth Grahame-Smith is action-packed: Review Imagine the story of the Nativity recast as a Hollywood blockbuster - a sword-and-sandals epic loaded with expensive computer-generated effects, a disfigured, lecherous villain and enough hacked-off limbs, severed heads and stomach-turning disembowlings to give even Quentin Tarantino pause - and you'll have a solid idea of what to expect in "Unholy Night," the new novel from mash-up king Seth Grahame-Smith. With his novels "Pride and Prejudice and Zombies" and"Abraham Lincoln: Vampire Hunter,"Grahame-Smith carved out a unique literary niche for himself, popularizing the genre mash-up movement and bringing a refreshing zaniness to historical fiction. For his latest, he channels his imagination in a similarly quirky fashion, this time following a master thief as he journeys from celebrated outlaw to reluctant bodyguard for the newborn Messiah. As leading men go, Balthazar is a perfectly compelling antihero, an ancient Syrian Han Solo type with a tragic past who's determined to settle an old score. As the story opens, Balthazar's outsized reputation as the famed thief known as the Antioch Ghost might finally be catching up to him, with a battalion of Judean soldiers on his tail and the beaten-down camel he's stolen as a getaway vehicle on its very last legs. Sure enough, he's soon captured, but an unexpected encounter with two fellow lawbreakers sets the stage for a grand escape in which they disguise themselves as - you guessed it - wise men, narrowly avoiding the death sentence imposed by the sadistic King Herod. How to describe Herod? Think Joaquin Phoenix in"Gladiator" (just as one-dimensionally Evil) but more withered and covered with boils. Their flight to safety takes them to Bethlehem, where an otherworldly star has illuminated the sky. In a stable hide-out, they discover a frightened young couple who believe their blue-eyed infant is the son of God. An avowed cynic, Balthazar dismisses their implausible claim, but he can't quite bring himself to abandon the family to the bloodthirsty squadrons who invade the town on Herod's orders. Not when soldiers are slaughtering innocent women and children in the streets. Fortunately, one of Balthazar's newfound allies, the squat, rotund Melychor of Samos, just happens to be the finest swordsman in the land; the other, the African Gaspar, is no slouch when it comes to battle either. Together, the three of them slice and dice their way through countless foes hoping to ferry Joseph, Mary and Jesus to Egypt, where they'll be beyond the reach of the wicked Judean puppet king Herod, the Roman Emperor Augustus Caesar and his scheming political subordinate Pontius Pilate. Grahame-Smith is a clever, enjoyably commercial writer who brought a surprising amount of complexity and depth to "Abraham Lincoln: Vampire Hunter." Here, he's scripted a fast-paced, rollicking adventure, but with every increasingly mind-blowing set piece, every revelation about the traumatic incident that so deeply wounded Balthazar, every leeringly arched eyebrow and depraved scheme that Herod hatches, the novel begins to feel too, well, scripted. There are moments of real humor and warmth and pathos, but too many of the characters, exchanges and story beats are disappointingly familiar. It's tempting to ascribe the novel's shortcomings to Grahame-Smith's bifurcated career: When he's not writing books, he's writing scripts, including the screenplay for Tim Burton's update of the cult TV series"Dark Shadows," released last month. With Simon Kinberg, Grahame-Smith adapted "Abraham Lincoln: Vampire Hunter" into a film due out this month, and he's announced plans to bring "Unholy Night" to the multiplex too. Perhaps his story's cinematic future proved too great an influence: His new novel reads like a big-budget summer movie, unrelentingly violent and entertaining enough in a grandiose, popcorn kind of way. But despite having some larger things to say about one man struggling to come to terms with his faith, it never quite manages to move beyond its action-flick tropes.