The study of the medieval Hell Mouth, the visual expression of the entrance to Hell, has generally centered on identifying its origins. However, that the visual Hell Mouth finds immense variation in form and context seems to deny any unilateral interpretation of the device. Art historians and scholars of visual culture have not before singly focused on the terrifying and visually compelling portrayal of the Mouth of Hell. While it is a longstanding and powerful referent in western culture, whether in text or image, and from medieval times to the present, no one has carefully examined its visual variants and their inimitable meaning for both Christian viewers and patrons, and for those less familiar with Christian teachings and belief. These four case studies drawn from medieval manuscripts offer close examinations of how the formal qualities of each variation distill the meaning of the Hell Mouth into visually legible form.