Arnold Schwarzenegger in Terminator Genisys.

More than three decades ago, James Cameron released a little slasher film with a sci-fi twist starring the dude from Conan the Barbarian.

The Terminator became a colossal hit—and the dude from Conan went on to bigger movies, including a rather high-profile temporary government job.

Terminator Genisys, the fifth film in the Terminator franchise, isn’t nearly as good as the original or the first sequel, Terminator 2: Judgment Day (also by Cameron). Thankfully, it’s a slightly better offering than the third and fourth Terminator films (Terminator 3: Rise of the Machines and Terminator Salvation), films in which Cameron was absent and off doing other things like Titanic and his jazzed-up alien-Smurf movie, Avatar.

Cameron himself was part of the marketing campaign for Genisys, because he admired the film’s faithfulness to his two original offerings. While I share his enthusiasm for some aspects of the movie, the film isn’t without major problems. In some ways, I’m kind of surprised Cameron liked this movie.

There are lots of tricks played using the time-travel gimmick, throwing the whole Terminator universe out of whack. This gives director Alan Taylor the chance to revisit and re-create events from the original Terminator, including naked Arnold Schwarzenegger’s first scene as the steely-eyed cyborg. The results are often fun, but a little chaotic and sloppy.

First, the good stuff: Arnold Schwarzenegger is back in his most iconic role, and he’s great. He plays a couple of different ages here, although he can’t get credit for playing his 1984 self in this film: That Arnold is a total computer creation, and an amazing one at that. Old Arnold fights his 1984 self in a scene I never thought I would see.

Arnie is as convincing as ever as an aging cyborg, with goofy pretend smiles and droll asides. As for action, the film provides plenty of good Terminator fights, and San Francisco again has a bad time at the movies, suffering through nuclear blasts and catastrophic school bus accidents on the Golden Gate Bridge.

Now, the bad: Emilia Clarke is a washout as Sarah Connor; Jason Clarke is miscast as John Connor; and Jai Courtney absolutely stinks as Kyle Reese. These are big flaws—flaws big enough to derail most movies.

Emilia Clarke seems disconnected, and there’s an insincerity in her line delivery. Jason Clarke plays John Connor like a cartoon character, which is disheartening after the good work done by Edward Furlong, Nick Stahl and even Christian Bale in the prior films. (Stahl and Bale were in subpar movies, but they still came off decently as John Connor.) His portrayal offers little nuance and feels out of place.

The biggest soul-sucker would be Courtney; he’s very bland in this one. Watch the original Terminator and Michael Biehn for a real angst-ridden, on-the-edge characterization of a guy who has been through the apocalypse. Courtney plays Reese like a soulless video-game character. There’s no reason to root for him.

Still … I like this movie. Arnold looks cool in his Terminator shades, and things blow up in really cool ways. Sometimes, I’m relatively easy to please.

Do the time-travel complications get a little confusing at times? Sure they do, but I admire Genisys for stretching out and attempting different things in the Terminator universe. Some of the paradox stuff had me scratching my head, but it all sort of ties together in the end. I did hate the total rip-off of the holographic villain from the Resident Evil series, though.

In the end, I had a good time. I want more for sure, and the movie leaves things open for future sequels, two of which there are currently planned. (Stay for the after-credits scene.)

If the future installments get the go-ahead, they should keep aging Arnie, but fire the rest of the cast. This film lacks true human charisma. As for Terminators, Arnie has things more than covered.

Terminator Genisys is playing at theaters across the valley.