The basic plot is that Porky Pig is having nightmares. Your job is to guide him through the nightmares, which consist of six worlds: a haunted forest, a Western ghost town, underwater, an abandoned mine, a snowy mountain/Wackyland, and a haunted castle.
An interesting aspect of the game is that the weather changes every time you turn on the game, and often weather will vary during the game itself. From one level to the next, it may be raining, snowing, or clear, and may have summer, autumn, or winter color schemes. Certain levels in the game play music from the song Brazil by Terry Gilliam.
Beta versions of the game featured different music arrangements and more hyperactive Porky sound bytes than the released version.