The Episode 5.20 will be called “The Devil You Know” and will air on 29th April 2010. Ben Edlund wrote the episode.

Source: Spoiler-TV

Official Description – Episode Stills – Trailer 01 – Trailer 02 – Clip 01 – Clip 02

This episode will also bring back the crossroad demon Crowley played by Mark Sheppard.

TV Guide just posted that the actor Matt Frewer was casted to play a role in the episode 5.20.

upernatural Exclusive: Matt Frewer Cast as One of Four Horsemen

Supernatural has cast another of the Four Horsemen of the apocalypse.

Matt Frewer — best known for a recent role in Eureka and for playing the title character on Max Headroom — has been cast as Pestilence, TVGuide.com has learned exclusively. Pestilence creates and spreads disease.

“Our first brush with him in Episode 520 seems relatively innocuous and then unfolds into something more substantial,” executive producer Sera Gamble said. “Put it to you this way: Horsemen on our show tend to think several moves ahead.”

Throughout Season 5, we’ve met two of the Four Horsemen. War (Titus Welliver) and Famine (James Otis) have appeared, while the fourth Horseman, Death, has only appeared off-screen in one episode.

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