To give a brief history of The Men of Letters - it is a secret organization of scholars who research the supernatural and while see the hunters as a necessary evil, revile the hunter's use of violence.

They were introduced in Season 8, Episode 12 where Abaddon possesses Josie and then goes on a killing spree. She follows Henry to a portal created by his blood spell to 2013 and kills him too. In episode 13, Sam & Dean travel to the Men of Letter's Bunker but find it abandoned - they do come across the Judah Initiative - rabbis who used to work with the Men during WWII.

Jump to episode 16 where in a bid to save Prometheus' son Oliver they find the translated journal of Greek hunter Dracopolis and finish the task at hand. Finally in episode 22, Sam & Dean discover that the Men of Letter's rating system and record of every demonic possession till their files were destroyed. They discover how to "cure" a demon and turn it human again - and so they put Abaddon back together.

Now the fourth Episode of Season 9 will deal with the history of the Men of Letters. Two of the Men of Letters will literally turn the key to the past of 1935. And what's more - there's going to the entry of Dorothy - a kickass hunter from a faraway and supposedly fictional land - you guesses it, Oz.

The Supernatural team is known for its really humour-twisted theme episodes - like Season 5, Episode 5 titled "Fallen Idols" had Paris Hilton play a demon. Or the Season 3, Epsidoe 13 "Ghostfacers" that was a twisted tribute to all the ghostly "real life" series on TV. And who could forget the looney "Huneteri Heroici" Season 8, Episode 8 - which was a tribute to all things wascally rabbit!

Show producer Jeremy Carver let in a sneak peek about how Sam feels about the Men of Letters' bunker where Dean is clearly at home with. Carver also called the Men of Letters storyline a "jolt of energy," with many new avenues in both story and character. And possibly yet another face off between Dean & Sam!

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