|“|| Valack: "Theo was a first step in the right direction for the Dread Doctors. Think of who they are-- parascientists who have prolonged their lives and twisted the laws of nature in pursuit of one goal... The creation of the perfect killer. And now they've done it"|
Lydia: "But Theo doesn't know who the success is...The last Chimera..."
Valack: "It doesn't matter. There's a reason they chose him, a reason he failed, a reason why they changed their methods, and a reason they finally succeeded. It all starts with Theo."
The Last Chimera is the eleventh episode of Season 5 and the seventy-first episode of the series. It is also the mid-season premiere, or the first episode in the second half of the season, also known as Season 5B.
- Tyler Posey as Scott McCall
- Dylan O'Brien as Stiles Stilinski
- Holland Roden as Lydia Martin
- Shelley Hennig as Malia Tate
- Arden Cho as Kira Yukimura (credit only)
- Dylan Sprayberry as Liam Dunbar
- JR Bourne as Chris Argent
- Melissa Ponzio as Melissa McCall
- Linden Ashby as Sheriff Stilinski
- Ryan Kelley as Deputy Jordan Parrish
- Cody Christian as Theo Raeken
- Khylin Rhambo as Mason Hewitt
- Susan Walters as Natalie Martin
- Kelsey Chow as Tracy Stewart
- Steven Brand as Dr. Gabriel Valack
- Victoria Moroles as Hayden Romero
- Todd Williams as Dr. Geyer
- Michael Johnston as Corey
- John Posey as Dr. Conrad Fenris
- Benita Robledo as Deputy Valerie Clarke
- Henry Zaga as Josh Diaz
- Jordan Fisher as Noah Patrick
- Marti Martulis as The Surgeon
- Douglas Tait as The Pathologist
- Caitlin Dechelle as The Geneticist
- Clayton Froning as Schrader
- Mirai Booth-Ong as Nurse Brenner
- Anthony Lapenna as Young Stiles Stilinski
- Lydia is committed to Eichen House by her mother Natalie after she is found in a catatonic state in the woods by Parrish where Theo left her for dead.
- Noah and Malia fight again, but this time, he regains control over his transformation before he can hurt anyone.
- It is revealed that Noah is part-Berserker, though what his other Chimera side is has yet to be revealed, though it may have something to do with the donor red bone marrow bags he was shown eating in Status Asthmaticus.
- Noah is presumably killed by the Dread Doctors, though the death was not shown onscreen.
- Theo discovers Scott is still alive after he finds the symbol of the McCall Pack, a circle inside another circle like Scott's tattoo, carved into the corrugated metal wall of the railway depot.
- Liam and Mason find out Hayden is alive when she (along with her sister, Valerie, and her fellow Sheriff's deputies) find them at the Nemeton, as Liam was desperate to find where Parrish brought her body in the previous episode.
- Parrish has another vision of Lydia, this time where she joins him in the shower and informs him that since he's a harbinger of death like her, he should know that someone is dying. He then found her in the woods, along with a rock with a carving of a Sheriff's badge to warn whoever found her that Sheriff Stilinski was dying.
- Josh Diaz is revealed to have glowing purple eyes as part of his Chimera transformation, though what supernatural creatures his Chimera nature is made up of have yet to be revealed.
- In this episode, Gabriel Valack tells Schrader that Lydia could shatter his skull with her voice if someone bothered to teach her how. Ironically, this will later prove to be true in Lie Ability, when Lydia (who was taught how to use her scream as a weapon by Meredith Walker while they were both catatonic and communicating through their telepathic Banshee connection) screams so powerfully as a result of the trephination that he performed on her that his skull is fatally shattered.
- Eichen House
- Closed Unit
- Lydia's Room
- Closed Unit
- Beacon Hills Memorial Hospital
- Reception Area
- Emergency Room
- Operating Room
- Lydia's Room
- Ambulance Bay
- Sheriff's Room
- McCall House
- Scott's Bathroom
- Upstairs Hallway
- Entrance Hall
- Parrish's Apartment
- Downtown Beacon Hills
- Beacon Hills Preserve
- Beacon County Sheriff's Station
- Parking Lot
- Beacon Hills High School
- Stilinski House
- Stiles' Bedroom
- Warehouse District
- Underground Sewers
- "Lost It All" by Jill Andrews
- Scott tries to make his eyes glow red with little success, and he defeatedly bandages up his wounds from Theo's fatal attack.
- "The Wreck" by Delta Spirit
- Scott, Malia, and Argent arrive at the hospital to learn the good news that the Sheriff will be okay.
- "Blow Up The Outside World" by Alex Clare
- Theo and the Chimera Pack confront Dr. Valack at Eichen House in the flashforwards.