Doctor Who: 10 Awesome Moments From Series 6's US Two-Parter

7. The Invisible TARDIS

When the Doctor took the TARDIS to the White House to delve further into the Space 1969 mystery his companions kept hinting at, he deemed it wise to put the TARDIS into "silent running mode". The TARDIS would materialise silently and would be invisible. Of course, the Doctor's plan did not work exactly as he had anticipated, and he ran into the side of the TARDIS when he was trying to get to the door. The invisibility plan worked better in Day of the Moon when its disguise made it possible to keep it hidden inside the Doctor's prison cell, making it almost too easy to escape. The really fascinating part about the invisible TARDIS was that invisibility was one of the original TARDIS designs back when the show premiered. Sydney Newman and Cecil Edwin Webber originally planned for the TARDIS to be invisible due to the Doctor having painted it with light-resistant paint. Ultimately, of course, they went with the now-classic police box design, but it was still pretty interesting to see one of the original design ideas being used in an episode 48 years later.