Fringe Connections

Walter implanted a tracker in his neck in "Snakehead" which is used in "Grey Matters".

The episode ends with September going into December's apartment, apartment 513, the episode code of the next and final episode of the series.

A hand can be seen outside the entrance to the daycare center.

Cecil mentions the Observers using a light bomb in "Through the Looking Glass and what Walter Found There", which is what Loyalists threw at Peter in the sewer tunnels in "The Bullet that Saved the World".

Olivia entered "Martin Luther King/Eldridge Cleaver Memorial Park" which has a plaque quoting them as saying "We have a dream" rather than "I".

A leaf can be seen on the bio-scan monitor at the Liberty Island security checkpoint.

The neon green fairy seen in the black market in "Transilience Thought Unifier Model-11" is like the green fairy Walter hallucinated in "Black Blotter".

When Nina looks in Bell's storage room for his copy of the First People book the camera pans by a copy of 'Dr. Spock's Baby and Childcare'.

The leaf glyph is on the electronic keypad at Massive Dynamic.

The tombstone in Olivia's dream state in "Pilot" says "He's Not Dead", possibly referring to John Scott, assumed dead, who appears at the end of "The Arrival".

It is true that the Empire State Building's spire really was initially designed for airship docking as it was in the Redverse.

A seahorse can be seen on Peter's luggage.

Peter said "You're going to be fine" to Olivia in "Brown Betty", like Charlie's "You're gonna be fine" message to Olivia in "Dream Logic".

Olivia pulled up a list of the frozen heads found in S02E04 'Momentum Deferred' and they were all marked with "2E204", a reference to the episode in which they were stolen.

The butterfly glyph can be seen on the wall in the diner where Olivia and Lincoln meet.

James Heath met with Lloyd Becker, a fellow Cortexiphan subject, in "Olivia. In the Lab. With the Revolver.". The name "Lloyd B." was on the height chart in "Jacksonville".

Jones is working with Bell, who is alive.

A flower can be seen outside the entrance to the daycare center.

Walter sent Peter the white tulip note from "White Tulip" in the mail and Peter received it in "An Enemy of Fate" after the future was successfully altered.

One of the envelopes Peter sorted through said "Thank you for your support!", a direct message from the creators of Fringe to all the fans.

The apple glyph can be seen on the backrest of a chair in the lab.

The bus in "The Ghost Network" was ambered. Huge sections of cities were ambered in the Redverse in "Over There (Part 2)".

This episode reveals that there is more than one Observer. The intro sequence since the pilot episode has had a single frame that says "OBSERVERS ARE HERE".

A frog can be seen in Walter's Monty Python trip.