Even the happiest marriage can feel like a war. But what if the relationship really was a killing field, with husband, wife, in-laws, friends and far-flung relations literally trying to exterminate each other? And what if that was really hard, because they're mostly undead?

This is the world of "Breaking Dawn, Part 2," where Mr. and Mrs. Edward Cullen work through some domestic issues in a combat-zone blowout sufficient to bring down a medium-sized country.

In the final film installment in the "Twilight" franchise, the evil Volturi vampire clan, feeling threatened by the birth of Bella and Edward's half-vamp offspring, mount a blitzkrieg on Forks, Wash. The Cullens recruit a league of allies with X-Men style magical powers to fight back. Since the only way to destroy a vampire in Stephenie Meyer's mythology is to separate the cranium from the shoulders, the film features more beheadings than a "Game of Thrones" marathon.

If you think the premise is absurd, wait till you see the execution. Logic and plausibility are not commodities valued by fans of the immensely popular "Twilight" series, and here they're abandoned entirely. The film's motto could be, "Look, don't think." Stars Kristen Stewart and Robert Pattinson are lavished with visual caresses by director Bill Condon and lenser Guillermo Navarro to an extraordinary degree, which certainly makes the picture's romantic scenes easy on the eyes.

We begin with Bella adjusting to her new status as a bloodsucker, having been turned by Edward to prevent her dying during childbirth. Oddly, Stewart's acting was more corpse-like when she was playing a mortal. Having crossed over to the undead, she's livelier and more expressive.

The newlyweds live in acute domestic luxury, occupying an idyllic forest cottage evidently based on a Thomas Kinkade painting. Their little mutant bundle of bliss, Renesmee, grows faster than humans do, reaching a toddler's size in just weeks. Eleven-year-old Mackenzie Foy plays the girl at six months of age. In earlier scenes and a flash-forward, Renesmee is an eerie fusion of child actors and wide-eyed digital face painting.

So for a time, the biggest challenge facing the couple is keeping Bella's policeman dad, Charlie (Billy Burke), from asking too many questions about why his granddaughter shot up 6 inches between Thanksgiving and Christmas. Since a comic scene of supernatural show-and-tell with Taylor Lautner's werewolf Jacob reminds us that Charlie is North America's least inquisitive cop, it's easier to believe he'll swallow anything.

A weird amalgam of hard action and soft romance, "Breaking Dawn" is most amusing when the Cullens, their ethnically stereotyped multicultural allies, and the swarming Volturi are hell-bent on mutual annihilation. Condon stages the frenetic battle royal with frenetic energy and no small amount of humor. The sequence is a showcase for Michael Sheen's campy, cackling vampire chieftain, Aro. Sheen makes a lark of his scenes. But there's too little of him and too much of everything else. "Breaking Dawn, Part 2" doesn't end the series on an especially strong note, but it ends it. Let's count our blessings.

ccovert@startribune • Twitter: @colincovert