Doctor Who: 14 Cool Details Revealed In David Tennant's The End Of Time Part One Commentary
5. The Vinvocci Originally Had Paler Faces
Near the end of the episode, it's revealed that two of the scientists working on the Immortality Gate are actually aliens called Vinvocci, who are bright green from head-to-toe, with dozens and dozens of spikes protruding from their heads.
It's a bold, eye-catching design that works surprisingly well, even in spite of how ridiculous it looks. But according to Lyn, that green colour wasn't always the plan.
Originally, the middle section of these Vinvocci faces (where the lighter shade of green sits in the final version) was going to be more pale and pinky, like human skin. But this was changed later on, and the Vinvocci were "greened-up" in post-production.