Пристрастившись к пиву и оказавшись в темном мире предательства и шпионажа, пол-литровая мышь промышляет разовыми работами и выполняет секретные задания вместе со своими подельниками.

События сериала крутятся вокруг антисоциального поведения одержимой алкоголизмом зеленой мыши-переростка по имени Фитцджеральд.

12 oz. Mouse revolves around Mouse Fitzgerald, nicknamed "Fitz", an alcoholic mouse who performs odd jobs so he can buy more beer. Together with his chinchilla companion Skillet, Fitz begins to recover suppressed memories that he once had a wife and a child who have now vanished. This leads him to seek answers about his past and the shadowy forces that seem to be manipulating his world.

O Rato Esponja é um desenho animado de humor adulto da adult swim criado por Matt Maiellaro (mesmo criador de Aqua Teen e Squidbillies). Sua produção foi de 2006 à 2007 com 2 temporadas, cada uma com 10 episódios.