The British Invasion

The British Invasion is the 17th episode of Season 12. It aired on April 6, 2017.

Summary
Sam and Dean get a lead on Kelly Kline’s (guest star Courtney Ford) whereabouts. Mick (guest star Adam Fergus) drops by the bunker unexpectedly and decides to join the hunt.

Plot
TBA.

Main Cast

 * Jared Padalecki as Sam Winchester
 * Jensen Ackles as Dean Winchester
 * Mark Sheppard as Crowley
 * Mark Pellegrino as Lucifer

Guest Stars

 * Samantha Smith as Mary Winchester
 * David Haydn-Jones as Arthur Ketch
 * Courtney Ford as Kelly Kline
 * Adam Fergus as Mick Davies
 * Shoshannah Stern as Eileen Leahy

Co-Stars

 * Ali Ahn as Dagon
 * Michael Meener as Dr. Turner
 * Darren Adams as Renny Rawlings
 * Gillian Barber as Doctor Hess
 * Eric Mazimpaka as Dermott Culp


 * Alex Barima as Lucifer's Demon

Featured Supernatural Beings

 * Archangel (Lucifer)
 * Crossroad Demon (Crowley)
 * Nephilim
 * Princess of Hell (Dagon)

Continuity

 * Eileen Leahy previously appeared in the season 11 episode Into the Mystic. Renny Rawlings references the events of this episode when he calls Eileen "the Banshee girl" and tells her that they have a file.
 * Dagon and Kelly Kline previously physically appeared in Family Feud.
 * Lucifer is shown licking the floor in this episode. He had previously forced Crowley to do this in Beyond the Mat.
 * The Colt returns to Dean's possession. He had previously used it in Abandon All Hope....
 * Castiel's cell phone responds with the same voicemail he had in First Blood.

Trivia

 * The episode had 1.58 million viewers and got a 0.5 rating.
 * The title is a reference to the phenomenon that occurred in the mid-1960s when rock and pop music acts from the United Kingdom, as well as other aspects of British culture, became popular in the United States, and significant to the rising "counterculture" on both sides of the Atlantic.
 * Much like John during Mary's death, Mary has developed a romantic relationship with someone else, specifically with Arthur Ketch.
 * This makes it the first time she had a sexual encounter with anyone in almost three decades.
 * Sam is shown to have a better understanding of sign language.
 * Mick previously stated that he had not killed anyone before prior to Hayden Foster, but this episode reveals that he may have lied, as his first kill is shown to be Timothy, his best friend, from Kendricks Academy.
 * Arthur Ketch revealed that he and Mick went to Kendricks Academy together.
 * Mick revealed that the key to the bunker can unlock every chapter house in the world.
 * Gillian Barber, who plays Doctor Hess, previously played Mrs. Rourke in Faith.

Errors

 * Lucifer calls Michael his "little bro". It has previously been established throughout Season 5 that Michael is the older of the two. This same error was made in Hell's Angel, an episode also written by the same writers.

Quotes
"The code is what makes a young boy kill his best friend."

- Mick Davies to Doctor Hess

"You only have to do what you know is right. You only have to answer to your own code."

- Sam Winchester to Mick Davies

"You think I wanted this to happen? He used me... but I love this child."

- Kelly Kline to Dean Winchester

"Well, that was unexpected. But invigorating. I must say, when I first met you I didn't see this coming. My thought at the time was, 'I'll end up shooting this one.' Life is full of surprises."

- Mr. Ketch to Mary Winchester