I was surprised; I was a little discombobulated by the fact that when the film came out, people said, 'This is an extremely terrifying, disturbing film', which was not my intention. I wanted it to engage the audience fully and I wanted Dorothy to be in a desperate situation, but the anguish of many of the reviews and some of the comments that I got from the film were... was surprising to me. And I'm still thinking about it. I have some ideas now after 30 years of why that might have been.

One of them is simply it isn't a musical and when there is something that has scary things in it but there's also singing, the singing says: this isn't so bad, it's just a show. And we didn't have songs. The other decision that I made for creative reasons was Dorothy was not a 15-year-old with a band around her developing breasts pretending to be nine years old. It was a real nine-year-old girl. The difference between a nine-year-old pre-adolescent girl and a 15-year-old pretending to be younger than she is, is substantial. Again because that's a real nine-year-old girl. Whereas if it's a 15-year-old girl pretending to be younger, you say, 'Well, it's just... it's pretend.'

So, as desperate as some of the situations are in Wizard of Oz, you have some escape valves from them, which is song and 'this is pretend.' And then the basic of much of the action in Oz looks like a vaudeville show. These are painted sets and they're clearly painted sets. We're not trying to fool anyone. This is paint. And so that adds another element where you think, oh, this is a theatre and if I want, I can get up and leave at any time because it's just theatre. Whereas a film that has a real, raging river and the girls really fall into the river – it looks real, I mean it's all a set and it's very artfully done but it's convincingly real. And that's a real house and that's a real doctor who's attaching real electrodes to Dorothy's... You know, that's also different.

And it's a scary world. When she gets to Oz, there are scary things that happen and there aren't very many cuddly things. There's... Toto gets left behind and is replaced by a chicken. And chickens, as charming as chickens can be... I'm a big chicken fan... They are not cuddly creatures in the same way that a cute dog is cuddly. And a robot Tik-Tok is different than a man pretending to be a Tin Man with a painted face. And Jack Pumpkinhead is a pumpkin and pumpkins are made to scare you on Hallowe'en and he's got this sort of grin, even though his voice is very nice, Brian Henson's voice; it's still a little scary. And the Nomes are scary and Mombi the witch is scary particularly because she has this ability to change heads at will, depending on how she feels: I'm going to use this head today.

And all of these are ideas that come from the books. I didn't invent these things. This is L Frank Baum and he had a definite ability to imagine these rather frightening things, even though he would say to his readers, 'I don't want to create any heartache in my readers. These books are charming and friendly' and yes, but... There are things looked at objectively that are strange. And that's one of the things that attracted me to the books. It was one of the things that, when my mother read these books to me at the age of five or six, I loved this stuff because it made me think in a very interesting way about, what is... If you could take your head off and put it somewhere else, what does that mean about who you are and what the head is and all of these questions?