Doctor Who Flux: 14 Best Easter Eggs You Might've Missed

14. Temperamental Nitro-9

One of the best easter eggs in the entire series can be found right at the start of episode one, The Halloween Apocalypse.

While the Doctor and Yaz are hanging upside-down after being captured by Karvanista, the Doctor mentions a "very temperamental" explosive called Nitro-9, something that she used to destroy Karvanista's droid guards.

Created by companion Ace and carried inside cans, Nitro-9 has been seen in the show before, and was first introduced in the Seventh Doctor serial Dragonfire.

From here, it was used several times - it proved powerful enough to destroy Daleks in Remembrance Of The Daleks, and even a Cyber-shuttle in Silver Nemesis.

Seems like the Doctor borrowed a few tricks from an old friend!