The scoop on CW‘s Supernatural is that the fan fave horror TV show will be airing an extra episode this season thus ending a week later then the rest of CW’s network TV shows. Below is Season 7 Episode 21 summary for Supernatural.
Supernatural - Reading is Fundamental (Episode 7.21)
5/4/12 - 9:00 - 10:00 PM
SAM AND DEAN SEEK OUT AN ALPHA - In order to defeat Dick Roman (guest star James Patrick Stuart) and the Leviathans, Sam (Jared Padalecki) and Dean (Jensen Ackles) must locate three key items. Castiel (Misha Collins) helps with one, but for the last objects the Winchesters must face two of their strongest opponents – an Alpha (guest star Rick Worthy) and Crowley (guest star Mark Sheppard).
Meanwhile Bobby (guest star Jim Beaver) tries out a new ghost trick that ends up being very dangerous.