Some sci fi TV shows are content to make us laugh, like Community creator Dan Harmon's ingenious Adult Swim sitcom Rick and Morty, Simpsons creator Matt Groening's Futurama, or the most recent season of Westworld.
Some are a little more serious in tone, but nonetheless maintain a largely upbeat and fun vibe throughout. After all, whilst the crew may get into some serious scrapes with the Borg, who hasn't watched The Next Generation and wanted to hang around with Riker and Picard, shoot the breeze with Data, and maybe send Wesley Crusher into space?
Then there are these shows. The anxiety-inducers and gasp-prompters. The shockers and s***-yourself-ers, the sci fi series which give the most hardcore horror shows a run for their money with how discomfited and edge-of-your-seat invested they get viewers.
Whether it's an anthology, a twisty mystery, or a genre-bending blend of the above, this list is a run down of the most anxiety inducing offerings small screen sci-fi has ever given us, to be watched through trembling fingers or not at all, for the faint of heart.