Mary Campbell: natural born killer.
After arriving at Mary's hotel, the Winchesters find it empty and their mother nowhere to be found. Moments later, Sam gets a call from Sheriff Jody telling him that Eileen Leahy was found dead in South Carolina after an apparent animal attack in an area that has never been known for it to occur.
We don't always do the right thing for the ones we love.
Since there mother hasn't checked in for more than a day, Alicia and Max Banes call Mary Winchester looking for help but instead, they get Sam and Dean. Dean is reluctant but Sam stresses that they have no leads on Castiel and may as well try to occupy themselves while they wait.
Ok, this girl has lost her mind.
After weeks without calling or texting, Castiel saunters into the bunker – much to the shock of Sam and Dean. Sam is happy to see him return but Dean has some harsh words for his angelic friend that made so little effort to get in touch with them. Castiel accepts the blame and admits that he was with the angels in heaven but they have nothing.
Sam: Dean, there could be a god up there.
Dean: I'm cool.
After getting a text from Mick about the latest strange killing, the boys are off to Tomahawk, Wisconsin to investigate.
You live by the code, you die by the code.
Just as they arrive back at the bunker, Sam and Dean see Mick sitting at the table. Mick begins to tell them about a cosmic shockwave that recently hot his radar but they already know – it's the Nephilim.
When a werewolf attack leaves one boy dead and his sister alive, the Winchesters will need the help of a not-so-old friend to solve the case.
After arriving in Wisconsin to look into the latest werewolf attack, the Winchesters, along with Mick Davies, have their work cut out for them. Dean isn't thrilled at the idea of a tag along but Sam has to babysit so it should be fine.
Every hell hound has its day.
Fresh off of a hunt and just getting back to the bunker, Sam gets a text message about a new case in Nebraska. Dean is curious about how Sam has something new so quickly but Sam brushes him off and tells him it's a new algorithm that he's developed to track incoming cases.
It's James Bond meets Assault on Precinct 13 in the week's episode, The Raid.
After Mary told her Sam and Dean that she had been working with the British Men of Letters and lying to them, you might say there was a bit of tension in the bunker. The Winchester brothers have dealt with quite a bit from the brits but there mother lying to them was the last straw.
Hey, teachers! Leave them kids alone.
After a teacher is found dead with his tongue ripped out and his organs crushed, the Winchesters have their latest case in Des Moines, Iowa. They ask Mary if she's up for taking a case with them but she's been busy killing demons with Mr. Ketch of the British Men of Letters.
When Dean gets hit with a magic spell that erases memory, Sam has to save his brother before there is nothing left.
After waking up in a forest with no idea how he got there, Dean manages to call Sam and have him meet him for waffles at the nearby diner. It's there that he sees a girl that he has no recollection of from last night and promptly gets a slap in the face.