Spock’s Brains

I am going to try to create a neologism here.
You have all heard of “jumping the shark”, a defining moment in a series where it goes off of the rails forever, never to come back to normalcy. (Or else it wouldn’t really be a jump)
However, I don’t think there is a term for a singular episode of a series which compared to far superior episodes of the series makes you go “WTF?” Sort of like Spock’s Brain in the original Star Trek.
So I am going to coin a term, a “Spock’s Brain”, to describe an episode of a TV series which is vastly weaker than others of the series. I realize that a Spock’s Brain can be subjective, too. To be a Spock’s Brain, it should be differently bad enough to stand out in that capacity.
Some Examples:
Star Trek: Original: Spock’s Brain. Remote controlled Spock! OY!
Star Trek: The Next Generation: Skin of Evil: Worst episode featuring a major character’s death, ever.
Doctor Who: The Web Planet: The Doctor, his companions and a bunch of people acting in insect costumes. Um, yeah.
Babylon 5: Day of the Dead: Um, one day in 200 years, dead come back for a night on one particular planet, and because of a weird arrangement, part of B-5 is transported technomagically across space to be part of it? Not one of Gaiman’s best ideas.
Suggestions from the Peanut Gallery for more “Spock’s Brains” would be more than welcome.