The line comes from Matt Berry's performance as the ancient vampire Laszlo Cravensworth in the FX comedy series What We Do in the Shadows, which premiered in 2019. Laszlo, a faded English aristocrat, peppers his speech with delightfully archaic curses, and "Hell's Horses" became one of his signature outbursts, quoted endlessly by fans. Clips of Berry shouting it spread through meme edits and reaction clips like You What, keeping the line alive as a go-to sound of theatrical outrage.