A few months ago, casting spoilers leaked to the Internet that Kripke and Co. were searching for the third Winchester brother.  Fans were livid.  Torches were sharpened.  Pitchforks were set on fire.  But before they could get a really good mob going, the title of the episode was also leaked: Jump The Shark.  The fans released a collective huh and then sat back to enjoy the carnage.

For those of you who don't know (because you live at the bottom of The Big Well in Greenberg Kansas) Jump the Shark is fan vernacular for the point at which a show becomes so bad that they result to ratings stunts to draw in viewership.  The term comes from the TV show Happy Days where in the ratings stunt that gave birth to the phrase, The Fonz water skied off of a ski jump and over a shark while wearing a leather vest and ski trunks.

This episode was named (in a very tongue in cheek way) because a common shark-jumping ploy is to introduce a new cast member to play the young, cute kid when all the other young cute kids have grown up (think Cousin Oliver on the Brady Bunch or Olivia on The Cosby Show).

And I tell you all this stuff you probably knew already just to point out that Kripke and co. were nudging us and winking at us for months over this.

In the episode, Sam and Dean get a call on John's old cell phone (nice continuity from Bad Day at Black Rock) from a boy who identifies himself as John's son.  The boys share a collective Buzhuh, and Dean goes into a snit (Dean's daddy issues were annoyingly front and center this episode) before they drive to Windom, Minnesota.  There they meet their earstwile sibling, Adam Milligan. 

Adam called John because his mother, Kate Milligan disappeared three days prior.  Once they determine that he's not demon possessed or a shapeshifter, they promise to help him find his mother.

Nineteen years prior, John was in town hunting something.  But two pages of his journal that detail the hunt are missing.  So Sam and Dean have no idea what, but they immediately suspect that it may be whatever it was that John hunted coming back for revenge. 

While Dean wants to cut Adam out of the hunt, Sam is all for educating him.  The two older brothers go their own way, Dean tracking the monster while Sam takes Adam under his wing, teaching him to shoot (in another nice call back.  This one to Dean's story about John teaching him to shoot in Bloodlust), setting him up to be bait (*cough*cough*red shirt*cough*cough) and reducing his home to a single point of entry: a big square vent under Kate's bed. (Who in their right mind puts a monster-under-the-bed-sized vent right under their bed?  Was Norman Bates the architect?)

Dean tracks the monsters to a crypt, where they trap him inside.  Meanwhile “Kate” returns to the home and she and Adam take Sam prisoner.  Surprise!  “Adam” and “Kate” are really ghouls.  Surprise again! The real Adam really was John's son.  But surprise a third time! He and Kate were killed by ghouls. (And the collective scream I heard on Thursday night was the sound of a million fans crying out from collective apoplexy.) 

The ghouls strap Sam to a table and try to bleed him dry while at the same time giving him one of the patented “teach Sam a life lesson about how drinking demon blood/cavorting in the throws of fiery demonic passion/acting stubborn like John is wrong” moments.   (Why he gets so many of these, I'm not sure.  He never seems to learn his lesson.)

Of course Dean saves the day, coming to Sam's rescue and killing the ghouls.  The two brothers burn Adam's body hunter-style, and Dean expresses the conviction that Adam is in a better place (more hints of Dean's growing faith).

This episode had the classic blend of humor and pathos that Supernatural is so well known for.  Keep your eyes open for lots of backhanded references to jumping the shark and cousin Oliver, including Dean wearing his leather jacket during the bookend scenes of the show.  And if you have the episode on Tivo or Hulu re-watch Jensen Ackles as Dean while playing rock, paper, scissors with Sam.  It's really subtle, but for about a second there Jensen/Dean pulls a classic gleeful expression before Sam throws rock to beat Dean's scissors.  The post-loss disappointed flail is funny in itself, but in that brief expression you can see that Dean is thinking that he's won the game.  Ackles never phones it in.  Why doesn't this man have an Emmy?

Additionally, there are plenty of references to the show's much-missed executive producer, Kim Manners, including the hotel's name (Kim Manor).

The show was also firing on all cylinders when it comes to creep factor: tight enclosed areas, monsters under the bed (and under the car, and in the walls), being buried alive.

But the thing that was creepiest to me was the level that Sam seemed to emulate John.  The single-minded determination and the willingness to let his newly-discovered, civilian younger brother play bait was all the more horrifying because it conjured up one train of thought in my mind: What if the real reason John didn't want Sam to go to college wasn't because he wanted to keep Sam safe?  What if it was because he knew that the Yellow Eyed Demon wanted Sam, and he wanted to (to borrow Sam's words regarding Adam) teach him to hunt and use him to draw in the demon?

The largest part of me doesn't think that this is so.  After all, this is John Winchester.  The man who loved his sons so much he couldn't let them have a normal life because he wanted to keep them safe. 

But then again, this is also a man who apparently had another son that he was content to keep in the dark and only see on birthdays.

It's that last thought and not the vent-lurking monster under the bed that's going to keep me up at night.