10 Most Horrifying Star Trek Moments

10. Spider-Barclay

Genesis is an episode that, on its own two feet, is perhaps not the best narrative of any episode of Star Trek: The Next Generation. However, between Beast-Worf and Spider-Barclay, there are scenes of pure disgust on show - ready to have the audience crawling out of their skins by episode's end.

Barclay's T-Cell virus is horrific, causing the infected to revert to earlier stages of evolution in their species. For some, this is somewhat inconvenient - Nurse Ogawa reverts to an earlier ape creature, though her unborn baby is the key to helping the crew. Troi reverts to an amphibious creature, while Riker doesn't change at all.

Sigh. Cheap shot, but here we are.

Worf, with his Klingon DNA being the gift that keeps on giving, reverts to a demonic creature that sprays acid and hunts people to consume them. Barclay's de-evolution is perhaps the most bizare.

Someone along Barclay's line must have gotten too close to a spider, as he reverts to a creature resembling a contaminated half-breed of human and arachnid. When Barclay slams against the glass in Engineering - Captain Picard was not the only one who screamed, that is for sure.