A.) Narrated by David Attenborough, the most amazing voice ever.
B.) Various sea worms, starfish and other tentacled things munching on corpse. Really beautifully, hypnotically disgusting.
"Three-foot nemertean worms and carnivorous sea stars prowl the Antarctic in search of flesh. Finding a dead seal, the sea stars inject it with digestive juices ... then suck it up like soup." (BBC youtube description)
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