The body count builds as a new human-hybrid shapeshifter seeks to perfect the technology that makes her possible. Former Massive Dynamic scientist, Doctor Malcolm Truss, unwittingly contributes to the cause. Nina Sharp makes amends with Walter and encourages his effort to connect with Peter.
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This episode's glyphs spell:
See the glyphs explanation for S4E08 - Back to Where You've Never Been.
The Observer can be seen behind Olivia at the crime scene outside the Truss home.
The labels "GOOD", "EVIL", "TRANSFORM", and "EJECT" on the wall in 'Subject 9' hint at the Shapeshifter plot in 'Novation'.
Locker #47, accessed by the Shapeshifter in 'Novation', foreshadows the 47 minute maximum time period of the time chambers opened in 'And Those We've Left Behind'.
Later, in the timeline without Peter:
In "Novation" Peter realized that the Observer's lack of action that night is what changed everything.