This episode’s poster is based loosely on Disneyworld’s 1950s Tomorrowland poster art. The Daleks obviously came a little later, but visually they’re very Sputnik-era aliens.
The tunnel of shrinking Doctors is taken from one of Jon Pertwee’s title sequences. As a childhood viewer of the Third Doctor, I think it’s a visual reference Peter Capaldi might approve of.
It is currently unknown whether there will be a poster for every episode of Series 8 of Doctor Who which continues tonight at 7.30pm with Into the Dalek.