Team Free Will is back and ready to dig into the history of the Men of Letters.

While Sam (Jared Padalecki) and Dean Winchester (Jensen Ackles) use the society's bunker as a home base, they know very little of the former inhabitants. The CW's hit sci-fi show will be fixing that dearth of knowledge during season 9.

"We'll discover how far the Men of Letters reach back into the Winchester's family history. And they'll be a source of new characters and [storylines]," said executive producer Jeremy Carver, according to the TV Guide's Comic-Con edition.

As the brothers discovered in last season's "As Time Goes By," their grandfather was a member of the Men of Letters and they were meant to grow up to join the secret society. The group accumulated knowledge surrounding the occult and supernatural, depositing a large portion of it in the bunker.

Fulfilling the promise to deliver more on the Men of Letters, Supernatural execs have just cast Gildart Jackson (Whodunnit) in the flashback centric episode 4, "Slumber Party."

Jackson will play the role of Haggerty, a 1930's member of the now defunct group, according to The Hollywood Reporter. Since all the known members of the society are all presumed dead following Abaddon's (Alaina Huffman) attack, it seems the only way to find answers is to look back in time.

Unfortunately, due to Castiel's recent loss of powers, there probably won't be any time traveling this season. Unless the Winchesters get their hands on whatever spell their grandfather used to propel himself to their current time.

Also, for your viewing pleasure, the CW has released the first official season 9 promo pic, which you can see above.  

Tags: supernatural