The Scavengers

The Scavengers is the name of a British public information film shown before horror movies in 1977. The ad is from a charity known as Lynx, attempting to stop animal fur trading. This ad takes things up a notch.

The ad starts off in a fly's point of view, hovering and buzzing over a city, as ominous music plays. The ad then cuts to a woman exiting a car and entering a building with a fur coat in hand. Meanwhile, the flies manage to enter the building and set their sights on a fur coat on a mannequin. After a couple of metaphors comparing the flies and the humans to using fur (including the people buzzing like flies as they talk), the woman finally notices something suspicious about that mannequin. She and a man she met walk over to it as the weird sound effects in the back increase in volume.

As soon as the woman pulls the mannequin's coat, a series of fast close-ups of the flies and maggots taking refuge in the mannequin appears revealed to be an animal carcass with a still-beating heart, which ends up falling to the floor. The disturbing scene is accompanied by electronic echoing screams. The ad ends with this message "When animals are killed for fur, two kinds of scavengers move in. The difference? The flies don't know better."

Link
NOTE : The following video contains extremely graphic content!
 * youtube.com/watch?v=NoCuAo1TUPg