The Girl Who Knew Too Much

Template:Infobox episode

“	Unbelievable. You have no idea what you are, do you? The Wailing Woman. A Banshee, right before my eyes. You're just like me, Lydia. "Look like the innocent flower, but be the serpent under't." It's too bad, though... And too late.	”
	— Jennifer Blake to Lydia Martin

The Girl Who Knew Too Much is the ninth episode of Season 3 and the thirty-third episode of the series.

Synopsis

As Allison begins to suspect someone dangerously close to her may be involved in the murders, Scott and Stiles conclude that Lydia's rising talents may be their best bet to solving the murders.

Plot

Allison and Isaac learn that the Darach is planning to sacrifice guardians next, they think that her father is involved with the murders, but end up discovering that he has been tracking the Darach for a while now. Meanwhile, Scott and Stiles want Lydia's help to solve the murders. Lydia discovers that Jennifer Blake is the Darach. Jennifer is about to kill her for knowing too much, and when Lydia screams in fear, Jennifer realizes that Lydia is actually a Banshee, aka "the Wailing Woman," explaining her attraction and inclination towards the supernatural. Stiles' dad tries to save Lydia, but is kidnapped by Jennifer, as he is a guardian. Scott goes to Ms. Morrell for some guidance, where she reveals that Deucalion's plan for him is that either Scott will join the Alpha Pack willingly after rising to Alpha status, or Deucalion will force Scott to kill, destroying his potential to become a True Alpha.

Cast

Main Cast

• Tyler Posey as Scott McCall
• Crystal Reed as Allison Argent
• Dylan O'Brien as Stiles Stilinski
• Tyler Hoechlin as Derek Hale
• Holland Roden as Lydia Martin

Supporting Cast

• JR Bourne as Chris Argent
• Melissa Ponzio as Melissa McCall
• Linden Ashby as Sheriff Stilinski
• Daniel Sharman as Isaac Lahey
• Bianca Lawson as Marin Morrell
• Charlie Carver as Ethan
• Max Carver as Aiden
• Adelaide Kane as Cora Hale
• Haley Webb as Jennifer Blake
• Keahu Kahuanui as Danny Mahealani

Guest Cast

• Ariel Flores as Student
• Mieko Hillman as Deputy Tara Graeme
• Meli Alexander as Teacher (uncredited)
• Laura Bedwell-Young as Beacon Hills Student (uncredited)
• Alex Borquez as Orchestra Member (uncredited)
• Roni Modlin as Choir Member (uncredited)
• Tina Q. Nguyen as Beacon Hills Student (uncredited)

Continuity

• Lydia is revealed to be a Banshee in this episode, and is the first Banshee to be introduced in the series. She first showed signs of being supernatural powers in Omega after she was bitten by Peter Hale in Formality.
  • Lydia also went into another fugue state in this episode, which drew her to Tara Graeme's body at the high school. She last went into a fugue state in this manner in Unleashed.
• Jennifer Blake is revealed to be the Darach in this episode, confirming that she has been the one performing human sacrifices throughout the season.
• It was also revealed that not only has Chris Argent been tracking the Darach's murders by keeping track of them using a UV marker and a map of the telluric currents on his desk (which was discovered in Currents), he has also figured out that the specific sacrifice rituals the Darach has been performing involves the Celtic five-fold knot, which is carved into the top of Argent's desk, and upon which he has written the five sets of three-fold sacrifices.
  • Virgins: Heather, Emily, and the lifeguard (Chaos Rising and Fireflies)
  • Warriors: Kyle, the band teacher, and Adrian Harris (Unleashed)
  • Healers: Dr. Hilyard and two other doctors (Currents)
  • Philosophers: Tara Graeme, Mr. Westover, and the recital pianist (this episode)
  • The final category is Guardians, the first of which she captured this episode in preparation for the final sacrifice-- Sheriff Stilinski.
• It is also implied by Jennifer that she gains various traits and powers from the sacrifices she's been taking-- virgins to help her maintain her "beautiful" appearance through a glamour; warriors to give her super strength and combat skills; healers to give her the power to rapidly heal her own wounds and the wounds of others; and philosophers to give her heightened knowledge and strategy. It is also implied that the future guardian sacrifices will give her the power to both protect herself from harm and just generally make her powerful enough to take on the Alpha Pack by herself.
• Sheriff finally learns about the supernatural in this episode after Stiles and Cora explained it to him using a chess board that has pieces with sticky notes labeled with all of the major players in the supernatural community of Beacon Hills. However, he doesn't believe it until he sees Scott shifts into his Werewolf form to save him. Stiles and Scott last considered telling Sheriff about the supernatural in Currents.
• Though it will not be revealed until The Overlooked, Cora was poisoned with mistletoe by Jennifer in this episode, making her the fourth victim to be poisoned in this manner.
  • The first victim was Kyle's dog Bullet in Unleashed, followed by Danny Mahealani in Currents and the recital pianist in this episode.
• Marin Morrell appears in this episode. She was last seen in Currents.
• Scott sees Ms. Morrell in the guidance office for information, and she confirms that Deucalion plans to either force him to willingly join the Alpha Pack, or Deucalion will force him to kill and destroy his potential to become a True Alpha. This plan was first hinted at by Deucalion in Frayed.
  • Though she implies that if Scott takes a life, he will no longer be a True Alpha, this fact has yet to be officially confirmed by anyone else in the series. It is possible that she told him this as a way to protect her own life.
• Ethan and Aiden reveal that they are not actually high school students, suggesting that they are older than 18 years of age. The twins enrolled at the high school in Tattoo.
• Ethan references Derek's deal with Kali, where he has until the full moon to kill the rest of his Betas and join the Alpha Pack. This deal was made in Currents.
• Stiles references Kate Argent, who was last seen in Season 1's Code Breaker, and Matt Daehler, who was last seen in Season 2's Fury. He also mentions Jackson Whittemore, who was last seen in Master Plan.

Trivia

• The title refers to Lydia Martin, who has unknowingly been drawing the Nemeton in a brief Banshee fugue states all season, which Jennifer sees. Jennifer then decided to kill Lydia, stating, "You're just the girl who knew too much."
• The conductor at the school's recital is played by Dino Meneghin, who composes the score for Teen Wolf.

Body Count

• Mr. Westover - three-fold death; killed by the Darach
• Recital pianist - slit throat; killed by the Darach

Locations

• Beacon Hills High School
  • Locker Room
  • Parking Lot
  • Ms. Blake's Classroom
  • Coach's Office
  • Guidance Office
  • Mr. Westover's Classroom
  • Auditorium
• Argent House
  • Allison's Bedroom
  • Chris' Office
• Stilinski House
  • Stiles' Bedroom
• Electric Substation
• Beacon Hills Memorial Hospital
  • Emergency Room
  • Reception Area
  • Cora's Room
  • Morgue

Soundtrack

• "Gentle Folks" by Hunter Hunted
  • Jennifer is teaching her English class at the high school, where she lectures about idioms and cliches.
• "Better With You" by of Verona
  • Lydia brings Aiden into Coach's office to make out and get answers about the Alpha Pack.
• "Let's Go" by Korn ft. Noisia
  • Aiden, thinking Derek is luring him into the locker room, goes to find him and finds that it's actually Cora who wants to attack him.
• "I Can't Find You" by SolarSolar
  • Jennifer rushes to the tunnel leading to the lacrosse field to meet with Derek, who she hasn't seen since Boyd's death.