Peter's gains support in the alternate universe and unites the two sides in an effort to eradicate the shapeshifter threat and their creator. Meanwhile, Walter assesses his life and decides to participate in the effort.
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Jones killed someone he loved in an act to demonstrate that nothing, not even death, could stop him from pursuing his goals.
The Observer can be seen walking behind Agent Lee as he chases after David Robert Jones through a crowd of people.
When Peter and Lincoln cross to the Redverse in 'Back to Where You've Never Been' they walk by Mohonk Tea House, foreshadowing Mohonk Quarry that's central to David Robert Jones's plan in 'Enemy of My Enemy'.
Signage for "Mallum Insurance" in 'Enemy of My Enemy' foreshadows the story of the Mallum family in 'Forced Perspective'.
He asked for a sign of forgiveness like he did in "White Tulip", but due to the different timeline he never got that sign.