[s2e20] | Brown Betty

: A gumshoe hired by Rachel (Olivia's sister) to find her missing love, Peter Bishop.

In Walter’s drug-addled fairy tale, the Fringe world is transformed into a sepia-toned 1940s noir: [S2E20] Brown Betty

: Nina Sharp is an evil industrialist, and the Observers are "Watchers" who strike from the shadows. : A gumshoe hired by Rachel (Olivia's sister)

: Peter has literally stolen Walter’s "glass heart," without which Walter will die. " without which Walter will die.