Supernatural - The Devil You Know

Sam and Dean got away from the Gods at the Hotel last week but now know that to defeat Lucifer, they will need all four rings from the Four Horsemen of the Apocalypse.  The already have two, War and Famine, now they need Pestilence and Death.
This episode was a bit of a set up the story type episode with not a lot happening to move the story forward.
Except that the demon Crowley showed up again and still wants to help the boys defeat Lucifer (even though the Colt he gave them last time didn't work!) because he is now on Lucifer's hit list.  He knows they need the other two rings so he offers to give them the demon who knows where they are, the 'stable boy' if you will.  Of course the plan doesn't go the way the boys think, but it is how Crowley planned it - can he be trusted?
Suffice to say, the boys get what they need so next week's episode will be pretty damn cool.
Crowley visits our friend in the wheelchair, Bobby, and offers to save the day as long as Bobby 'lends' him his soul.  He promises to give it right back - can he be trusted?
As I said, not a lot happened and we had a visit from the invisible hell hounds again (cheapest special effect ever - what a cop out!) and of course no Castiel, AGAIN!  What's with that?  Still, it's a great show and there are only two episodes left of season five to go.  Bring it on!