It's amazing. It's the only film ever to be vetoed by the Mystery Science Theater 3000 cast and crew, who considered it too awful and disturbing. They're wrong when they call it awful, since it's explosively brilliant and it blew me away.

However they're right to call it disturbing, because of the extensive nudity from a twelve-year-old girl in a movie with a paedophile theme.

Firstly, the reasons to be cautious. It's directed by first-generation exploitation filmmaker Harry Jack Revier, who did most of his work in the silent era but most of that's been lost. Lash of the Penitentes (1936), for instance, is built around someone else's footage of flagellant monks in New Mexico and a nude female crucifixion scene. At the same time it's also the first film produced (albeit on reissue) by Kroger Babb, also famous in this subgenre and the writer/producer of Mom and Dad (sex hygiene exploitation film that might be the third highest-grossing film of the 1940s). These people have a reputation. You might have guessed that they're not paying much attention to the Hays Code.

Secondly, there's the content of the film itself. It's claiming to be moral and educational, as is normal for 1930s exploitation films, but it was still controversial and widely banned. (It did very nicely on the exploitation circuit instead.)

It's about under-age marriage, as the title suggests. Adult males are forcing themselves on twelve-year-old girls. The film is preachy on this subject, especially through the person of Diana Durrell's schoolteacher. She's so passionate about it that she's kept her fiance waiting for five years because she's more interested in staying in this mountain community and trying to reform its hillbillies. The guy's still chasing her, amazingly enough. The guy's a saint. "Perhaps we might still be able to stop this child marriage!"

What's different about Child Bride is that this theme is explosive enough to survive some preachiness. Reefer Madness is silly. Sex Madness is dull and annoying. Child Bride is electrifying, especially towards the end, when the plot actually goes there. We see the wedding. "You may kiss the bride." My skin crawled all the way off my body and hid behind the sofa. We then see the bridal bed. Holy flaming cow. Until now I'd never seen an adult man bring a doll to his bride-to-be, saying "look what I brought you." Just as importantly, though, it's not just the controversial subject matter, but the fact that we're watching it being played out by Warner Richmond (age 52) and the remarkable Shirley Mills (age 12).

Richmond is strong and the best-established actor in the cast, having been in the business since 1912. Mills though is astonishing. Sometimes she's a dreadful ham, but she's also capable of owning the screen in a manner 90% of professional actors would envy. (She'd have a solid career as a child actor and is also in The Grapes of Wrath, although she retired in her early twenties.) She's vivid. She made me laugh out loud with her delivery of "Freddie, did you do your spelling lesson?" because she's so intense in her relationship with her co-star. I assumed the actors were siblings in real life, but apparently not. Her performance in the last act couldn't be called flawless, but she's the one who makes it work. What she achieves here is beyond the level of most movie stars.

...and then there's Mills's nudity. I knew about the skinny-dipping scene, although I hadn't expected it to be so important. Throughout it, you see, Mills is having a conversation with her best friend (male) about how her teacher's told her she shouldn't go swimming naked with boys. In other words, the dialogue is addressing the children's attitudes to the issue of sexualising small girls, even as the camera sexualises a small girl. It's a key scene. You couldn't possibly cut it. If you did, you'd remove a cornerstone of what the film's saying. (Underneath its preachiness, this film is giving us a surprisingly meaty analysis of its themes.)

No, the scene that got to me was Mills's introduction, where she wakes up in the morning and stretches (unconvincingly) in front of a sunny window in a thin nightdress. That's way more disturbing, for being entirely gratuitous and also for what it's showing. You could defend it as a self-aware expression of that "sexualising young girls" theme, deliberately challenging the audience to force them into self-analysis, but this is probably more sophistication than was intended by Harry Jack Revier and Kroger Babb.

If you've got that in the film, does the rest almost writes itself? Nope.

I've been discussing the dynamite at the heart of the movie, but what brings it roaring to life is its Ozark hillbillies. Rednecks are great and these are top-notch. They shoot each other. They murder their partners and blackmail the widows. They gather in mobs to kidnap pesky schoolteachers, with plans that include boiling tar. (She's been saying things to their women, trying to teach them modern ideas like "it's wrong to have sex with pre-teen girls".) It's awesome just being in this world, which if it were British would start out with The Wurzels on the soundtrack. I was grinning at little things like a beaten-up Huckleberry Finn hat. These people have a ton of personality, making ordinary movie characters look flat and dull.

I love the cast too. Based on the evidence of this film, Revier appears to have been a good director of actors. The film even includes a dwarf, Angelo Salvatore Rossitto (Tod Browning's Freaks, several films opposite Bela Lugosi and as the upper half of Master-Blaster in Mad Max Beyond Thunderdome). All films improve when they have a dwarf in them.

Also of note:

1. The necklines. I'm guessing it's warm in the Ozacks, because the women wear low-cut dresses that might fall interestingly off the shoulder. Of course for the film to leer at adults doesn't justify naked twelve-year-olds, but it shows that Harry Revier was an equal-opportunities exploiter.

2. The scene that hinted at going beyond even this film's already extreme limits. Mills's father is lying on the floor and it's bedtime. Mills tries to do her duty. "Wake up, daddy, it's your little Jennie. She wants you to come to bed." "I suppose I'll have to undress you and put you to bed." If you can watch that without fear at where it might conceivably be heading, you're stronger than me. Here, as elsewhere, the key is that Revier's putting natural child behaviour in a context where you're expecting horrors.

I think this is a superb movie. I'm not being ironic either. I genuinely think it's brilliant, although it's blasting off its own foot with Mills's nudity. Nevertheless if (big "if") you can stomach that, it works like gangbusters. Mills is capable of being both the film's biggest flaw and the best thing in it, but fortunately the latter predominates. There's so much here to go crazy for. I love the way that the story pulls out a Get Out Of Jail Free card at the end... and then completely ignores it, instead leaving its hillbillies unaware of any change in the law and instead letting their horrors play out to their conclusion. I love the way that the preacher's words at a graveside are to give Biblical injunction to blood feuds. I love the fact that our idealistic, noble teacher is also terrible at her job. (Look at her teaching methods! Maybe that was acceptable in 1938, but today?) It ends with a happy murder and it'll give you the heeby-jeebies. Wow.

"We have our own ideas about what's right and wrong in these mountains."