During the on-the-scene news broadcast reporting mountain lion sightings in the greater Boston area, The Observer may be seen passing behind the news reporter.
Walter talks about the work he did for Kelvin Genetics. 'Kelvin' is a name featured in many J.J. Abrams productions, because Kelvin was the surname of his maternal grandfather.
In this episode, Kiersten Warren plays Sonia, Kirk Acevedo 's (Agent Charlie Francis) wife. They've been married in real life since 2005.
The glyphs in this episode spell "Peter".
Walter sings "Van Amburgh's Menagerie", which he used to sing to his dog Rufus; the song was popular in the late 19th century and is about real-life lion tamer Isaac Van Amburgh.