As soon as you use an element on the screen it becomes subject to dramatic laws. This is as true of colour as of everything else. So I wanted to shoo… - Rouben Mamoulian

Colour cinematography tends to brighten and cheapen natural colour. The problem was to counteract that. I realised that colour in films is nearer to painting than to the stage. Now if you look, for instance, at a crimson cloak painted by El Greco, you’ll find that what first appears as a mass of colour is in fact a subtle blending of all sorts of shades, with patches of pink and blue and purple and green. So I treated the colour the way a painter would.

To accompany the transformations I wanted a completely unrealistic sound. First I tried rhythmic beats, like a heartbeat. We tried every sort of drum, but they all sounded like drums. Then I recorded my own heart beating, and it was perfect, marvellous. Then we recorded a gong, took off the actual impact noise, and reversed the reverberations. Finally we painted on the sound track; and I think that was the first time anyone had used synthetic sound like that, working from light to sound.

Garbo asked me: "What do I play in this scene?" Remember she is standing there for 150 feet of film – 90 feet of them in close-up. I said: "Have you heard of tabula rasa? I want your face to be a blank sheet of paper. I want the writing to be done by every member of the audience. I'd like it if you could avoid even blinking your eyes, so that you're nothing but a beautiful mask." So in fact there is nothing on her face: but everyone who has seen the film will tell you what she is thinking and feeling. And always it's something different. Each one writes his own ending to the film; and it's interesting that this is the scene everyone remembers most clearly.