As originally promised in 1984, Arnold Schwarzenegger’s Terminator is back (again).

“Terminator Genisys,” the latest in the seemingly endless “Terminator”  series, brings former California Governor Arnold Schwarzenegger back for a fourth turn as the infamous deadpan cyborg. And, as is to be expected of the newest addition to the rapidly aging franchise, “Genisys,” though mindlessly fun, suffers from a contrived and underwhelming narrative that fails to reignite the spark lit by its iconic predecessors.

The series “reboot” follows Judgement Day survivor and human resistance soldier Kyle Reese (Jai Courtney) back in time to 1984 in what is, essentially, a recreation of the plot of “The Terminator” (the original film): protect Sarah Connor (Emilia Clarke) from assassination, father future resistance leader John Connor (Jason Clarke) and stop the terminator sent by the artificially intelligent network Skynet.

When Reese arrives, however, the world he encounters is not the one he expected. Rather, the Sarah Connor of “Terminator Genisys” is prepared for his arrival, is being protected by a reprogrammed T-800 (Arnold Schwarznegger) and is on a mission to time travel to 1997 and stop Skynet before it triggers Judgement Day, the fabled nuclear holocaust so persistently referenced in “Terminator” films. Despite this unplanned shift, Reese convinces Sarah that traveling to 1997 will, ultimately, stop nothing. Because the future Skynet has meddled with past events, a new timeline has been generated, and Skynet will inevitably take over in 2017 thanks to machine-uniting computer program Genisys. Undeterred, Sarah and company elect to travel to 2017 regardless, and, once there, she incidentally runs into the future John Connor — who, in what should’ve been the movie’s biggest twist (had the marketing team not already previewed the massive spoiler in the film’s trailers), is revealed to be a new type of terminator (part human, part cyborg) sent to guard Skynet and take out the ragtag band of heroes. The ensuing battle is one against humans, machines and, of course, time.

In general, the fear factor so memorable in series creator James Cameron’s “The Terminator” is missing. Few things are more chilling than an expressionless, unstoppable robot that genuinely “can’t be reasoned with,” but a menace like the T-800 featured in the original is noticeably lacking. This is primarily the fault of the upgraded terminator models; their more humanoid composition makes them far less threatening. After all, artificially intelligent villains are at their best when they simply can’t “feel pity, or remorse, or fear”– not when they can display human emotion. Even if the terminators had maintained their dispassionate ruthlessness, their shock value has been watered down, as the images have, over time, been rendered redundant by the first two films.

In addition, the script, penned by Laeta Kalogridis (“Shutter Island”) and Patrick Lussier (“Drive Angry”), is littered with contradictions. Sarah knows details about the future that she couldn’t possibly be aware of unless she had popped in a DVD of “The Terminator” on her day off, and the T-800 arbitrarily throws around terms like “quantum physics” and “nexus point” in a half-baked effort to justify the direction of the story. Further, the script’s heavy reliance on time travel as a cure-all plot device means that the film maintains little to no continuity or cohesiveness. Kalogridis and Lussier establish limitations and boundaries on time travel and then wholly ignore them, introduce important questions (who sent the T-800 to protect Sarah in the first place?) and then forget to answer them and expect us to believe that this attempt to stop Judgement Day is somehow more feasible than the last two dozen attempts without ever explaining why. Instead, the resolution leaves the majority of these holes wide open, hopefully to be repaired in the inevitable “Terminator 6,” “7” and, if the studio is lucky, “8.”

From this wreckage of a narrative, the A-list cast is only able to salvage a few touching moments. The film’s heart rests precariously on Emilia Clarke’s charming father-daughter-like relationship with Schwarzenegger (which is particularly enjoyable on-screen); however, through no fault of her own, the more critical relationship between Clarke’s Sarah and Courtney’s Kyle is insincere and their interactions, one-dimensional.

Courtney is underwhelming, and his take on the easily likable Kyle Reese lacks the spirit of a soldier ready to sacrifice himself for a love he barely knows. His best scenes all lean heavily on the skills of the other actors (Jason Clarke in particular), who struggle to keep Courtney from completely sapping these encounters of their inherent vibrancy.

Even the more-than-capable Schwarzenegger, who — at 67 years old — still delivers an impressive performance, is wasted on the script’s many poorly-written scenes. Many of Schwarzenegger’s lines serve to either clarify the disorienting plot or provide comedic relief, and the once cold-blooded killing machine that captivated audiences — not because it killed dozens of people, but because it didn’t care that it did — is largely absent.

With that being said, while “Genisys” takes a heavy blow for its inadequate writing, the visual effects team’s contributions serve as decent compensation for the missing wow factor. In one sequence, a half-human, half-terminator John Connor drags himself away from the magnetic pull created of an MRI machine, and each partial silhouette perfectly matches Jason Clarke’s physique in a visual that is both surprisingly terrifying and instantly memorable. In another, a young Schwarzenegger — digitally de-aged by the magic of CGI — brawls with the real Schwarzenegger in an undeniably entertaining set piece rife with startling originality.

“Genisys” isn’t short on delightful bits of nostalgia either. Director Alan Taylor makes a sincere and genuine effort to pay homage to the original films; characters repeat classic one-liners (“Come with me if you want to live!”), revisit famous locales (including the apocalyptic wasteland that is the year 2029 — crushed human skulls and all) and recreate unforgettable scenes (featuring CGI-young Arnold). Surprisingly, these frequent tributes do not present themselves as unnecessary fan service, but rather reinforce the film’s updated interpretation — the well-integrated references inject much-needed life into a dragging script that reaps great benefit from putting a modern spin on old tricks.

Unfortunately, impressive effects and clever nods are far from enough to bring audiences back for the inevitable sequels born of this lackluster reboot. Maybe it’s time to finally say “hasta la vista.”

Contact Shannon O’Hara at shannonnohara16 ‘at’ mittymonarch.com.