I first have to agree with a previous review, I love the Charger as a vehicle being driven in the episode. I love the Impala and miss seeing it, but this was a heck of a temporary replacement.
On to the review. It was great to see Cass back. I didn't like how he just walked into the lake and disappeared. Cass kind of became a staple on the show, like Bobby. I'm hoping to see him pop back in. The question is, how did Cass come back? Was it God? Who some of us thought was the writer of the Supernatural books (I forgot his name). Thanks to the end of Season 4, I think, when he "poofed" at the end. We got the chance to see Mark Pelligrino showing up as Satan again. What a voice to have in your head. He has a creepy laugh that I wouldn't want to hear. I left out a lot of the juicy parts of the episode on purpose, but if you read reviews to decide if you should watch an episode you might have missed, you will want to watch this. If you've been away for a while, catch up on the ones missed first.