Short Movie Filler Day - The Tell Tale Heart

This animation was released in 1953 and it's based off of Edgar Allan Poe's "The Tell-Tale Heart".

According to the Youtube description:

The story told by a mad man has a dark visual with a perfect work of narration by James Mason. It is a UPA Production and was the first cartoon to be X-rated (adults only) in Great Britain under the British Board of Film Censors classification system.

To say the least, this animation is one of the most chilling animations that I've ever seen.