We have the first Battlestar Galactica episode of 2009, Sometimes a Great Notion, which marks the beginning of the end of this fourth and final season, for your viewing pleasure right here. Click below to watch this new episode in its entirety, with the added bonus of commentary from series creator and executive producer Ronald D. Moore.

Both the humans of the Colonial fleet and their Cylon allies fight against the emotion of overwhelming despair as they try to understand what happened to the 13th Tribe.

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Dee reconciles with her husband Lee Adama despite being devastated about the discovery of Earth. Kara finds a puzzling and disturbing clue regarding her identity.