8 More Horror Movie Fan Theories That Make The Films Even Creepier

8. Sarah Killed Everyone - The Descent

Joining her five friends a year after losing her husband and child in a tragic accident, Sarah embarks on a caving trip to rekindle the group’s relationship. What’s supposed to be an action packed (but safe) adventure to a known cave system soon turns sour when the entrance collapses and traps the women inside. It’s revealed they’re in a completely unknown, unmapped part of the underground, sharing the space with a bunch of pale humanoid creatures with a taste for human flesh, leaving the women to be picked off slowly until only Sarah remains.

The theory goes, however, that instead of the monsters wreaking havoc on the caving group, it’s actually Sarah after a psychotic break.

Obviously portrayed as suffering from PTSD, Sarah crawling through the entrance and becoming trapped in the sheet rock is potentially the catalyst to snapping her mind completely, and being trapped in the cave leads her to kill all her friends, as they die one by one. Her continual visions of her daughter’s birthday cake reinforce Sarah’s break from reality - finalised at the end of the film where she hallucinates her escape before seeing her one last time.

Interestingly, the candles on the cake change from five to six in this final shot. Five friends murdered, and six deaths when Sarah succumbs to her last moments in the cave. The Descent’s title also parallels not just descending underground, but Sarah’s descent into madness.

That Sarah is the first one to see a crawler and Juno tries to convince her it’s her eyes playing tricks on her is the cherry on the blood-soaked cake.