Synopsis of two of the up-coming episodes have been released (or updated):
Episode: 5.09 The Real GhostBusters
Teleplayed by Eric Kripke!!!! Oh my master, I pledge myself to your writing, your wit and your awesomeness.
Sam and Dean at a Supernatural Convention - fans are not possessed, they are just crazy!
Synopsis: Super fan Becky (guest star Emily Perkins) uses Chuck’s (guest star Chuck Benedict) phone to trick Sam and Dean into attending a Supernatural fan convention, complete with fans dressed up as Sam and Dean. One of the activities is a live action role playing game, but things quickly turn sour after a real ghost appears on the scene. Teleplay by Eric Kripke and story by Nancy Weiner. Directed by Jim Conway.
Episode 5.10 Abandon all Hope
Sam, Dean and Castiel track down the Colt and head off to find Lucifer to send him back to Hell. It’s a hunters’ reunion when the crew joins forces with Bobby (Jim Beaver), Ellen (guest star Samantha Ferris) and Jo (guest star Alona Tal) for what could be their last night on Earth.
Source: SupernaturalTV, Hunters Addict.
Welcome back Ellen and Jo! I hope they are not going to die! But we know two of our favorites will die in this episode. I have high expectation on this episode. Sounds like it's gonna be really epic!