It seems like a lot of people are dumbstruck by filleted fish.
More precisely, filleted fish that still move. Here's the video everyone is flipping out over:
-- ??? Yutaka Suzuki (@Q57OUPrpy8OZaWt) July 5, 2017
It's not like the fish is still alive.
Okay, it is a little strange to see one side of a fish, no head or guts, flopping around. Still, there's no need to scream about it. It's natural.
Even though the innards are gone, cells inside the fish can still respond to stimuli. The muscle neurons still contain something called membrane potential. That means the neurons have charged ions, and stimuli, like sodium, can open the channel to the muscle.
Which results in twitching, headless, gutless fish. Until the electrical balance is restored. The effect happens to a lot of less-than-intact critters. Frog legs will jump. Squid will fling its legs around.
Even a human corpse will randomly move and twitch for hours after death. Bet that flopping filleted fish doesn't seem so creepy now, does it?