Includes all 12 seasons, 279 original broadcast episodes. Bonus Features: - 12 hours of extras from all seasons, plus a bonus disc with exclusive never before seen features. - The Big Bang Theory: A retrospective - final reflections from the cast and producers - All the stars in the BBT Universe - the cast and crew highlight the many guest stars who have been on the show - BBT's greatest hits: 12 years of comedy in 24 minutes - a collection of the funniest moments from every blockbuster season. - 32 page episode guide with an introduction from creator and executive producer Chuck Lorre and new behind the scenes cast photos. Brand new and unopened.