The 10 spookiest Doctor Who episodes to watch on Halloween - as voted for by YOU
We asked the fans to rank the scariest episodes of all time and here's what made their Wholloween watch list
4. The Waters of Mars (2009)
The Doctor meets the first group of humans to have settled on the Red Planet, led by Captain Adelaide Brooke. From historical records, the Time Lord knows that today is the day they all die – but he doesn't know how. The crew become infected by a fast-acting, waterborne, water-producing virus that transforms them into aggressive monsters, and the Doctor meddles with fixed points in time.
Jennifer Tevault Ralph nominated The Waters of Mars because it "plays on everyone's fear of a global epidemic".
"There's something truly terrifying about something that infects humans," explains Laura Hughes. "To this day I've only seen the episode twice (in comparison to other episodes that's very few) because it scares the living daylights out of me."
