1. All the cartoon action was storyboarded to link-in with the live-action. In this scene Roger is hiding in Hoskins’ kitchen sink. He pops up and spits out a mouth-full of water.
2. A metal pipe was rigged for the live action shoot to spray out water.
3. A photostat was made of each frame of the film so the animators could position their drawings accurately.
4. After extensive line testing each drawing was photocopied onto cel and painted. These were filmed in Vista Vision. First a front-lit version was shot.
5. Using the painted cel (shown in 4.) as a mask a back-lit version was shot. This was used later to add the background.
6. In this version of the final composite Bob Hoskins’ fingers are hidden by Roger’s neck. This was a mistake on the original drawing.