|“||"Can you help her?"
"We can try."
"If not, she stays."
"What... What does that mean?"
"If we can't help you, you'll stay and become one of us. A Skinwalker."
"You'll walk with us under the sun, through the dust."
Codominance is the thirteenth episode of Season 5 and the seventy-third episode of the series.
- 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
- Dylan Sprayberry as Liam Dunbar
- Tamlyn Tomita as Noshiko Yukimura
- Cody Christian as Theo Raeken
- Khylin Rhambo as Mason Hewitt
- Kelsey Chow as Tracy Stewart
- Victoria Moroles as Hayden Romero
- Michael Johnston as Corey Bryant
- Maya Eshet as Meredith Walker
- Michelle Clunie as Mrs. Finch
- Tiffany Phillips as Dark Spirit
- Emily Alabi as Black Night
- Tonantzin Carmelo as Skinwalker #3
- Marti Matulis as The Surgeon
- Douglas Tait as The Pathologist
- Rahnuma Panthaky as Ms. Fleming
- Clayton Froning as Schrader
- Mandy Levin as Nurse Cross
- The episode title refers to Mrs. Finch's lesson on codominance in terms of genetics, where instead of dominant alleles overpowering recessive ones, they are both present, and sometimes even combine to make something new. This could be a reference to the Chimeras, or to the dual personality of The Beast of Gevaudan and its host, Kira and her inner Fox spirit, or Parrish and his Hellhound spirit.
- Scott and Stiles reference a serial killer known as the Demon Tailor during their research of the concept of damnatio memoriae. This killer is said to be a real person who brutally assaulted children, boiled them, and ate them during the late 16th century in France, and is also known as the Werewolf of Châlons. However, sources of information on this killer are not proven to be completely accurate.
- Shiprock, New Mexico, where Kira was seeking help from the Skinwalkers, is in Navajo Nation, a semi-autonomous territory in the southwestern United States that belongs to the Navajo tribe of Native/Indigenous Americans. This suggests that the Skinwalkers also belong to the Navajo tribe.
- Mr. O'Quinn - mauled/decapitated; killed by The Beast of Gevaudan
- New Mexico
- Gas Station
- Skinwalkers' Desert
- Beacon Hills, California
- Beacon Hills Animal Clinic
- Exam Room
- "Too Deep" by Ritual & Delilah
- Mason and Corey make out in the locker room after discussing Theo and the Beast.
- "If God Don't Follow Me" by Adam Road
- Kira returns to Noshiko with the severed head of the Desert Oni and tells her that she did it, but the Skinwalkers tell her that she failed the test because it was the Fox, not Kira herself, who slew the Oni.
- "Recover" by XPLOR
- Liam and Hayden have a serious discussion and kiss in the library.
- "Shut Out of Paradise" by Slo
- Kira and Noshiko jump into Stiles' Jeep so they can join Scott and Stiles in fleeing the Skinwalkers, and Kira and Scott kiss passionately to celebrate their reunion.