Doctor Who Series 10: 14 Easter Eggs & References You Might've Missed In 'Smile'

8. Another Ark In Space

When the Doctor realises what the colony is, he comments that he has met a couple of similar refugee colonies of human beings escaping the end of the Earth before. This is actually an idea that goes all the way back to the First Doctor’s era.

1966’s The Ark sees the TARDIS land on a spaceship that is escaping the sun swallowing the Earth. Like in Smile, the human’s servants – the Monoids – want independence. The idea is revisited in 1974’s similarly-titled The Ark in Space. That story, in particular, featured the humans stored in cryogenic pods during their journey, as in this episode.

In more recent years, The Beast Below – yep, that one again – saw the UK bundled into a starship and set off across the stars.