My first horror movie? Disney's "Return to Oz."

I was in elementary school when I first watched Walter Murch's dark, visionary 1985 film, which was marketed to children despite being one of the most legitimately terrifying "family movies" of all time. It rattled me, deeply. I couldn't stop watching it.

Released on June 21, 1985 to mixed reviews and poor box office, "Return to Oz" was the first and last directorial effort from esteemed Oscar-winning sound and film editor Walter Murch, who cut such acclaimed movies as "Julia," "Apocalypse Now," "The Unbearable Lightness of Being" and "The Talented Mr. Ripley." It was not, as they say, your grandmother's "Oz" movie. The Wicked Witch of the West may have been frightening for very young kids, but she was nothing compared to the devilish, head-swapping Princess Mombi, the sadistic, baritone-voiced Nome King, and, god help us, the cackling Wheelers, a group of fluorescent roller-derby mutants who served as nightmare fodder for an entire generation of children.

Make no mistake: "Return to Oz" is scary -- very scary. It was also heralded as being much more loyal to L. Frank Baum's original books than 1939's "The Wizard of Oz," which it was inevitably -- and generally unfavorably -- compared to. Indeed, then-nine-year-old Fairuza Balk told "Entertainment Tonight" while promoting the film that she was "very very very very very sick and tired" of Judy Garland comparisons, "because I'm not competing with her. I think she was probably a wonderful lady. She did a wonderful movie, and now I'm doing a wonderful movie, and sometimes it's probably hard for people that have grown up with the 'Wizard of Oz' to adjust to a new movie. I mean, not everybody's going to like it."

The production period, as Murch has described in previous interviews, was tortured. So much so that five weeks into filming, Disney was so unhappy with what they had seen that they fired him from the film. Only a last-minute intervention from former USC classmate George Lucas -- who promised Disney he would step in and "take control" of the production if things continued to go downhill -- allowed him to continue. Once it was finished, the studio failed to adequately promote the film and on it flopped on release, earning a mere $11 million off a $28 million budget.

"...this film lived through two changes of management, as I said, so that by the time I was in post-production, there was a whole new management at Disney," Murch told Film Freak Central in 2012. "And they were not really interested in 'Return,' probably because it was so dark, and not a musical, and particularly because it had been started by an executive two generations earlier, and so they mostly ignored it after it did not do so well in previews, which was both good and bad. The good part was that I was able to complete the film I wanted to make, the bad part was that they didn't really get behind its release. Having said that, it was a difficult film to distribute, as we found out, given the zeitgeist of the mid-'80s. Maybe any zeitgeist."

And yet 30 years on from its initial lukewarm reception, "Return to Oz" remains one of the most unheralded near-classics of "family" cinema, a beautifully shot, magnificently scored film (anchored by nine-year-old Fairuza Balk's supremely assured performance) that has what so many movies aimed at children lack: a real sense of wonder and imagination. And of course it doesn't shy away from darkness, a quality that makes it unsuitable for very young children but which also gives it a sense of real depth and real stakes. Watching the film again for the first time since I was a child, I was shaken by Murch's strikingly dark, imaginative imagery, pummeling sound design, blistering score and Oscar-nominated special effects. It's no wonder it had such an effect on me.

In celebration of the film's 30th birthday, I can't think of a better tribute than to highlight eight of the film's most strikingly dark sequences, from the early asylum-set first act to the final showdown with the Nome King. These are scenes that seared themselves into my brain and made the film an unforgettable viewing experience. Not only that, but they retain their visceral, bone-chilling power to this day.

1. The electroshock sequence

After Aunt Em (Piper Laurie) foolishly leaves Dorothy overnight at a psychiatric clinic run by the deceptively serene Dr. Worley (Nicol Williamson), the young girl is strapped down to a gurney in preparation for -- yes! -- electroshock therapy. Meanwhile, the screams of men imprisoned in the clinic's basement filter up from below. Did I mention that Worley's assistant, humorless Head Nurse Wilson (Jean Marsh), is the most terrifying woman of all time? Because she is.

2. Escape from the clinic

After the power suffers a short from the thunder and lightning storm raging outside, a mysterious young girl frees Dorothy from the gurney and helps her escape the wretched facility as Nurse Wilson -- wearing a dress that would not look out of place at a turn-of-the-century Satanist colony -- gives chase in a sequence that is legitimately nerve-jangling. David Shire's killer gothic-tinged score goes a long way in amping up the scare factor.

3. The ever-present Nomes

The Nome King's loyal sentries can manifest in any rock formation throughout the land of Oz, meaning their creepy distorted faces are constantly popping up to keep tabs on Dorothy and her friends. The intermittent reports of the main "Nome Messenger" are rendered in hellish Claymation, lit by the fiery glow of the King's private lair. Shu-dder.

4. The Wheelers

The most notorious of "Return to Oz's" coterie of baddies are undoubtedly the Wheelers, who first appear in the sequence where Dorothy and her clucking sidekick Bellina come across the ruins of Emerald City. We only hear the eerie sound of their creaking wheels at first, but when they finally do make an appearance, oh my god. Oh my god oh my god oh my god.

5. Princess Mombi's castle

Though she seems harmless enough when we're first introduced to her, Mombi shows her true colors once she switches heads and informs Dorothy that, no big deal, she's just gonna lock her up in the tower for a few years until her head is ready to lob off and place in a glass cabinet. Her creepy mandolin playing probably should have been a red flag.

6. Escape from Mombi's castle

"Dorothy Gaaaaallle!" Mombi is scary initially and even more terrifying once she dons the horrific visage of Jean Marsh (a.k.a. Nurse Wilson), who -- like an angry, snarling pitbull -- tries to take a bite out of Dorothy's hand when she catches her stealing the Powder of Life. The visual of the entire hall of heads screaming in unison as Dorothy makes her escape -- intercut with the headless Mombi rising from her slumber to give chase -- has never left me. This is arguably the film's single most traumatizing moment, and Shire's jolting score is, once again, a true standout.

7. Princess Mombi's race to the Nome King's lair

Did I mention that Mombi is terrifying? After Dorothy and friends escape from her castle, the wild-eyed ruler races headlong toward the Nome King's lair with the help of her slaves the Wheelers, whom she whips mercilessly as she goads them to move "Faster! Faster!" As shot by Murch, the sequence -- intercut with a quieter scene inside the King's lair -- is a red-hued vision of frantic insanity that wouldn't look out of place in a "Hellraiser" movie. What award can we give Jean Marsh for this?

8. The Nome King flies into a rage

In the movie's big climax, the sadistic King, backlit by flames, grows to a gigantic size while bellowing furiously as he discovers Dorthy and pals have outsmarted him. Cackling maniacally, his face twisted into an expression of pure hatred, he then grabs Jack Pumpkinhead and dangles him over his gaping maw. A fortuitous egg laid by Bellina drops down the King's throat, leading he and his rockbound minions to moan "Poison! Poisonnnn!" over and over as they crumble into oblivion. It is an appropriately hellish sequence that caps off what is, in my estimation, one of the scariest children's movies ever made. Happy, happy anniversary to this dark cinematic dream.

A former contributor to sites including MTV's The Backlot and Bloody-Disgusting, Chris Eggertsen worked in film development before indulging his love of pop culture writing full time. He specializes in horror, the intersection of social issues and entertainment and Howard Stern. He's on Twitter @HitFixChris.