The best sci-fi movies are treasures. For a few wonderful hours, they take us out of the dull monotony of the real world, allowing us to escape into just-barely-believable universes where anything is possible.

Sci-fi movies are big business, and they tend to dominate the summer blockbuster season.

Just look at some of the films due out in the next few months: Avengers: Age of Ultron, which follows a team of superheroes as they fight an evil robot. Tomorrowland, based on the futuristic section of the Disney World theme park. Jurassic World, where we’ve brought dinosaurs back to life, tearing nature horribly out of balance and offering Tyrannosaurs some tasty human-shaped snacks.

And there are plenty more where those came from.

While you’re waiting for the inevitable Avengers-Star Wars crossover, though, why not check out some of the best sci-fi movies on Netflix?

Best Sci-Fi Movies on Netflix — Terminator 2: Judgment Day

This July, moviegoers will be treated to a brand-new entry in the Terminator franchise. Terminator Genisys, starring Khaleesi Emilia Clarke, releases July 1. (Yes, I’m one of the optimistic ones; Terminator Salvation really lowered the bar for future sequels).

The first film in the series, 1984’s The Terminator established a dark, compelling universe with a devastatingly unstoppable villain. And Terminator 2: Judgment Day took the best pieces from that film and built them into a sci-fi classic.

Judgment Day stars Linda Hamilton as a badass determined to save her son and the rest of humanity from the oncoming apocalypse — no matter what the cost. It co-stars Arnold Schwarzenegger as a reformed (more accurately, a reprogrammed) villain with an inexplicable Austrian accent.

If you like visceral action scenes, Terminator 2 has plenty of ‘em. Lots of things that go boom, too. And if, like me, you’re primarily interested in the characters and how they develop through the course of the movie, don’t even worry. There’s as much heart in this film as there is in any Oscar-nominated drama.

Let’s just hope that Genisys director Alan Taylor studied what made Judgment Day so great.

Best Sci-Fi Movies on Netflix — Star Trek II: The Wrath of Khan

In a time where movies are crossing over with movies and TV shows are crossing over with their movie crossovers, we should acknowledge the amazing feat achieved by Star Trek II: The Wrath of Khan.

The Wrath of Khan took a character who had appeared in precisely one episode of the Star Trek TV series and, 15 years later(!), resurrected him as one of the most beloved movie villains of all time. To understate things, that’s pretty amazing.

To put that into context, that’s like Joss Whedon making a new Buffy the Vampire Slayer movie, bringing back a one-off villain as the big bad. And then that villain making every “Best Villains” list between now and 2050.

So if you’re on the lookout for the best sci-fi movies on Netflix, you should probably give Wrath of Khan a look.

Best Sci-Fi Movies on Netflix — The Fifth Element

Depending on how you like your movies, The Fifth Element might not be an obvious choice for the best sci-fi movies on Netflix. It’s weird, it’s campy and it’s absolutely overflowing with ‘90s retrofuturism.

And that’s kind of why I love it.

In fairness, I also love it because I’ll watch Milla Jovovich in just about anything. Ditto Gary Oldman, who takes his villain stratospherically over-the-top in this film.

But the bottom line is this: It’s a fun movie. After more than a decade of “grimdark” sci-fi tales and superhero films, it’s nice to sit back and watch a movie that wants to be fun. Keep your grit. Keep your brooding. (Well, there is some brooding; it stars Bruce Willis, after all.)

The Fifth Element is all about fun and spectacle, which makes for some unapologetically great sci-fi.

Best Sci-Fi Movies on Netflix — The Hunger Games: Catching Fire

The Hunger Games novel reminded the world that books marketed toward teens and pre-teens can be just as entertaining and engaging for adults.

The first movie adapted that story with debatable success.

The Hunger Games: Catching Fire, however, did a much better job at translating the mythology and the pain and the characters that made the books so popular. Jennifer Lawrence does a wonderful job of showing us just how much Katniss has evolved since the first book, even as the aftermath continues to take a toll on her. And Jena Malone steals scenes as the axe-wielding Johanna Mason.

The characters are brighter, the action is more visceral, and the whole film just outshines the original entry. If you’re looking for the best sci-fi movies on Netflix, odds are you won’t be disappointed in Catching Fire.

Best Sci-Fi Movies on Netflix — Robocop

For the final entry, I’m turning things over to InvestorPlace managing editor and Robocop fanboy Kyle Woodley:

“X” ratings are usually the realm of risque adult films, yet Robocop director Paul Verhoeven had to cut down violent scenes and spruce up the jokes to avoid one.

That’s how rough ‘n’ tumble Robocop was.

While it doesn’t have nearly the level of special effects achieved with today’s technology, it more than made up for it with sheer brutality — not just to the villains, but our hero as well.

The gruesome murder of officer Alex Murphy evolves into a cyborg redemption story set in a dystopian Detroit (let that sink in) in which law enforcement is turning toward robotics (let that sink in) and corporations reign supreme (let that sink in).

Along the way, blue- and white-collar baddies alike get their comeuppance in an ugly way, and the fine representatives of humanity are able to overcome criminal corruption, nefarious programming and really, really big guns.

Robocop is a blood-splattered mess, but an insanely gratifying one.

(And it gave us this.)

More From Investorplace