chorus
Explanation
The Joke
Two people are watching a TV show -- most likely a classic sitcom. One of them enthusiastically describes the show: "Oh, come here! I just love this show. Every time someone tells a joke, a chorus of voices from beyond the grave sing out in praise!" The other person responds with an impressed "Cooooool..." The caption at the bottom delivers the punchline: "If you watch an old enough sitcom, everyone on the laugh track is dead."
The comic reframes the familiar sound of a sitcom laugh track in a macabre light. Laugh tracks were often recorded in the 1950s and 1960s, meaning the people whose laughter you hear on classic TV reruns have long since passed away. By describing the laugh track as "voices from beyond the grave," the comic transforms something mundane into something eerily supernatural.
The Humor
The humor is in the jarring recontextualization. The laugh track is one of the most ordinary, even annoying, features of television -- but when you stop to think about it, you really are listening to dead people laugh. The comic frames this realization as if the character is describing a ghost story or a supernatural phenomenon, and the fact that it is technically true makes it land harder. It is the kind of observation that, once you hear it, you can never watch an old sitcom the same way again.