Fringe Connections

The End-of-Dayers targeted the Orpheum Theater in "The Day We Died", a soft spot from when Olivia and the other Cortexiphan subjects crossed over to get Peter in "Over There (Part 1)".

The crane that crashed during the intro has a Massive Dynamic logo on it.

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

The posters from Peter's Redverse bedroom in "Subject 13" were hung on the wall when Walternate took him back in "Over There (Part 2)" in order to bring a sense of comfort and familiarity to Peter.

The green and yellow posters in the diner represent how this new timeline with the yellow/amber title sequence is starting to merge with the original timeline with the blue title sequence now that Peter has returned (blue + yellow = green).

Butterflies can be seen on a box in September's apartment.

Olivia's mindscape in "Lysergic Acid Diethylamide" shows an area with Iraqi architecture, a reference to when Olivia met Peter in Iraq in "Pilot".

Bell stole Walter's David Bowie album 'The Man Who Sold the World', which describes what Bell did multiple times for his own benefit.

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

The opening scenes of "Letters of Transit" reference Casablanca (a man named Rick owning an upscale nightclub). Peter and Fauxlivia watched Casablanca together in "The Abducted".

All of the people in Olivia's mind wear blacks and greys because Cortexiphan subjects have a strong desire to blend in.

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

Olivia's pregnancy dream in "The Same Old Story" is in a waiting area with giant tulips.

The flower glyph glitches away after the scene where Olivia's fear caused her to interrupt all the electronics in the room.

A seahorse can be seen on Peter's luggage.

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".

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".

Butterflies can be seen in Etta's apartment.

The blue powder dispersal doll from "Concentrate and Ask Again" was seen in Walter's storage vault in "The Bullet that Saved the World".

The briefcase contained photos of Walter.

The butterfly glyph can be seen as Olivia and Shapeshifter Charlie fight in the alley.

The Observers read Nina's phone call from the impressions her sound waves made on the glass in her office in "Anomaly XB-6783746", like Peter did in to hear the phone call Nancy Lewis made in "The Road Not Taken".

There are 'Wanted' billboards for the Fringe team.

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