ITunes service will allow you to purchase items that are already in your purchase history. In this case all but two episodes of a sitcom were purchased - I believed I was purchasing a season pass for the upcoming season when in fact I purchased a season pass for something (for the most part) I already own.
I canceled the downloads and unfortunately purchased the individual episodes I was after confidant that I would receive a refund - no dice.
In Katie's Words:
"I've carefully considered your request for a refund for your duplicate purchases of the first part of Battlestar Galactica, Season 3. While I understand that you were not aware that you would be charged twice for these videos, I regret to inform you that your request has been denied. As stated in the iTunes Store Terms of Sale, all sales are final......"
Thanks for that apple. A curse on you and your family.