The episode concerns a mysterious cylindrical object called "The Beacon" which appears at a construction site in New York City.

The story also involves the relationship between Walter Bishop (John Noble) and the mysterious Observer (Michael Cerveris in his first feature appearance).

At a diner in Brooklyn, New York, a bald man with no eyebrows sits down at a table and orders a raw roast beef sandwich with eleven jalapeño peppers and a glass of room temperature water.

When the sandwich arrives, he drowns it in Tabasco sauce and black pepper and wolfs it down in large, quick bites, to the bemusement of the diner staff.

During this time he is also watching the construction site across the street through high-tech binoculars and taking notes from right to left in unrecognizable characters.

In their shared hotel room Walter keeps Peter awake by reciting the chemical formula for root beer.

The next morning Peter expresses his unhappiness with the arrangement to Olivia (Anna Torv) and tells her he wants to leave.

In the course of the investigation, Walter assaults and forcibly sedates Junior Agent Astrid Farnsworth (Jasika Nicole) in order to hide the cylinder.

At the end of the episode, Olivia returns home, and sees recently deceased lover John Scott (Mark Valley) in her kitchen.

[4] When initially cast for Fringe, Cerveris assumed he was a mere guest star, and that his character was "one of several nuggets dropped in" by J. J. Abrams in a manner similar to his other science fiction series, Lost.

Executive producer Jeff Pinkner commented, "Our goal was to take a character who is by definition unknowable and make him someone you can connect to emotionally.

To simulate the energy gun the Rogue fires at Olivia in the forest, the crew placed pyrotechnic charges near the trees to make it appear large blasts were close to hitting her.

Patterson from "Generation Kill" toting around a futuristic-looking ray gun and a retro-looking mind-reading machine, Walter casually injecting whatsername with a sedative—that I think I'll be sticking around for a bit...

Murray wrote, "'The Arrival' was the weirdest episode of Fringe yet–a deep-down sci-fi spookfest that minimized the show's procedural side and instead raised far more questions than it answered.

The shock and awe factor of "The Arrival" was strong, but as a piece of storytelling, the episode felt slight and soggy, and hardly the satisfying standalone experience that the creators promised each Fringe chapter would be.

Fickett also noticed many similarities to The X-Files, writing "not enough is being done to move the show into its own direction"; he concluded "The production values are exceptional, the acting is top notch, and it certainly seems to be going somewhere.

His altercation with Peter in the graveyard — mirroring his movements; parroting his speech in real time — was one of the show's earliest water-cooler-weird moments.