Lifty and Shifty are the identical twin raccoon thieves from Happy Tree Friends, the dark cartoon series known for cute characters meeting sudden, slapstick disasters. Their matching voices and constant scheming made them easy to recognise, and short clips of their panicked screams began circulating as reaction sounds on soundboards and in meme edits. The scream works because it needs no context: two voices shouting at once instantly signals that something has gone badly wrong. That simple, exaggerated panic keeps it useful for fails, scares and chaotic punchlines years after the show first appeared.