Bloodless performances, a weak script, and a shady obsession with eternal relationships makes The Twilight Saga: Breaking Dawn — Part 2” one that is at its best when it’s at its worst.

According to the Twilight Saga Wiki, “The only known way to kill a vampire is to dismember his or her body and burn the remains before it can reconstruct itself.” This was apparently ruled too complicated a procedure to pull off repeatedly on the silver screen, and so the death process has been simplified to mere decapitation in “The Twilight Saga: Breaking Dawn — Part 2.” Indeed, taking the easy way out seems to be the modus operandi of the final installment. Bloodless performances, a weak script, and a shady obsession with eternal relationships makes the film one that is at its best when it’s at its worst.

“Breaking Dawn — Part 1” concluded with the birth of Bella (Kristen Stewart) and Edward’s (Robert Pattinson) half-human, half-vampire daughter Renesmée (Mackenzie Foy) and Bella’s transformation into a vampire. The sequel picks up precisely where its predecessor left off. In the film’s opening sequence, Bella awakens to a supercharged reality, her newly perceptive eyes flickering from individual grains of wood to shimmering droplets of water before settling on a strangely pore-free Edward.

The first half-hour is oddly devoid of conflict. Bella settles into life as an immortal and a parent. However, a threat soon emerges in the form of the Volturi—the ancient coven of vampires that enforces the laws of the blood-sucking community. These aren’t your typical bureaucrats as when the Volturi mete out justice, it is invariably in the form of a beheading. Believing Renesmée to be a forbidden “immortal child,” they plot to snuff out the entire Cullen coven.

It’s a sparse premise, but the saga’s first four films have never challenged its audience with a narrative that resists delineation in five sentences or less. Rather, as a 116-minute-long pat on the back, “Breaking Dawn — Part 2” doesn’t develop characters so much as work to assure the viewer that these are the humans, vampires, and werewolves they know and love. Scenes contain dialogue, of course, but serve primarily to trigger fans’ pleasure centers via familiar tableaus. Feast your eyes as Edward and Bella embrace, as Jacob (Taylor Lautner) and Bella come to blows, as various Cullen siblings pull off supernatural feats, and as red-eyed villains glower beneath hooded cloaks.

Solid acting can overcome a sub-par script in an adolescent-targeted movie—Antony Hopkins in “Thor,” for example. Sadly, “can” is the operative word in this film. Lautner, it seems, is truly an actor for whom actions will always speak louder than words—the only time he appears natural on screen is when engaged in the act of undressing. The dramatic abilities of Stewart and Pattinson are generally less panned due to well-received performances in “Into the Wild” and “Water for Elephants.” However, when Stewart derides Jacob with the potentially fiery line, “I’ve held [Renesmée] all of one time and already you think you have some moronic wolfy claim to her?”, she characteristically exhibits all of the enthusiasm of a McDonald’s employee working the Thanksgiving shift.

Thankfully, there is a faint silver lining: combine mechanical delivery with Melissa Rosenberg’s anemic screenplay, and the result is a veritable treasure trove of unintentionally hilarious moments. Of particular note are the sequences that bookend the requisite Bella/Edward sex scene. A tour of the bizarrely idyllic cottage the Cullens have built Bella and Edward as a wedding present concludes with the master bedroom. Bella: “Vampires don’t sleep.” Edward: “It’s not intended for sleep.” Two minutes later, the pair is seen cuddling before a roaring fireplace. “You really were holding back,” breathes Bella. The absolute seriousness these scenes attempt to convey is rendered farcical by Pattison’s and Stewart’s jarringly blasé attitudes.

Even still, the dialogue is occasionally funny on purpose. In order to prevent Bella and Edward from expatriating themselves, Jacob desperately reveals that he is a werewolf to Bella’s father Charlie (Billy Burke). Tossing aside his shirt, he declares, “You don’t live in the world you think you do.” This is a case where the audience laughs with instead of at Rosenberg, but scenes in this deliberately absurdist vein are too few and far between.

Infinitely more disturbing than a weak plot or sub-par acting is the central theme of “Breaking Dawn — Part 2.” Those at the helm of the Twilight Saga have apparently decided that the main attraction it has for its fans is its promise of “forever.” This is what is stressed in Edward and Bella’s relationship—not the depth of their passion, not their shared antipathy toward outward displays of emotion, but the soulless fact that they will be together until the end of time. For proof of this, look no further than the anthem of the film, “A Thousand Years” by Christina Perri. “I have loved you for a thousand years. I’ll love you for a thousand more,” Perri croons as Bella and Edward embrace in a field of eerily bright flowers. While other adolescent movies’ weak plots can be salvaged by a story of heroic triumph or upstanding morality, the emphasis on a pointless forever assures that the film remains shallow to its core.

Because of this disturbing trope, “Breaking Dawn — Part 2” cannot pass even as harmless amusement. While the eponymous book does not dwell solely on the concept of an eternal relationship, the movie’s fixation on this particular idea leeches the film of the romance that could have lent pre-pubescent slumber party appeal. Frankly, the only comfort to be gleaned from this film is that the Twilight Saga is something that will not indeed last forever.