In a controversial move, Scott denies Liam’s plea to bite Hayden to save her life. He’s afraid the bite will kill her since she is already a "failed experiment". Parrish and the Nemeton Lydia and Parrish finally track down the Nemeton .
Scott believes Theo over his best friend. He refuses to listen to Stiles’ side, leading to a rift that feels like the end of the pack. The Chimera Crisis [S5E9] Lies of Omission
Stiles killed Donovan in self-defense, but his guilt has kept him silent for weeks. In a controversial move, Scott denies Liam’s plea
Theo claims Stiles brutally murdered Donovan in cold blood. Scott believes Theo over his best friend
The heart of this episode is the devastating confrontation between in the pouring rain. Theo’s web of lies officially traps Stiles when he shows Scott the bloody wrench from the library.
She is bleeding mercury, a sign that she is next on the Doctors' list.
Parrish has been subconsciously stealing the bodies of the failed Chimeras and taking them to the ancient stump.