iTunes Season Pass - The iTunes Season Pass is a feature of the iTunes Store that allows users to purchase a full season's worth of a given TV show at the iTunes Store before all episodes have been released.
The Season Pass feature allows users to pre-pay for the season's worth of content, usually at a discounted price, and then download the episodes from the iTunes Store as they become available. This purchase is made at the show's page in the iTunes Store. All currently available episodes will automatically download. Later episodes are downloaded automatically as they are released on iTunes.
This feature is only available for shows that are currently being broadcast on TV or cable. Shows that are no longer producing new episodes are not eligible for Season Passes.