FBI special agent Dale Cooper (Kyle MacLachlan) has been sent to the town to investigate[3] and has discovered that the killer was Laura's father, Leland Palmer (Ray Wise), who acted while possessed by a demonic entity—Killer BOB (Frank Silva).
Cooper's doppelgänger, exhausted from the process, crashes his car and passes out, allowing the police to capture him;[6] at the station, he uses the information in his possession to blackmail Warden Murphy (James Morrison) into releasing him and his partner, Ray Monroe (George Griffith).
On their way through, Ray stops to urinate; the doppelgänger uses this occasion to attempt to extort the information he was seeking from him, and, when he refuses to cooperate, tries to kill him, but the gun provided by Warden Murphy has had the firing pin removed and does not work.
In an imposing windowless building atop a craggy outcrop amid a purple sea, Señorita Dido (Joy Nash) sits next to a metallic-bell shaped machine, listening to a phonograph.
He then begins to levitate, light and tendrils of energy emanating from his head like a forming galaxy, as stars are projected onscreen.
After kissing the orb, she sends it to Earth (which appears on the screen) through a golden tube contraption emanating from the whirring luminaire ceiling.
Two woodsmen manifest and descend on a rural road, stopping a couple's (Tad Griffith and Leslie Berger) car.
He asks the receptionist (Tracy Phillips) for a "light", then crushes her skull, killing her instantly; overpowering the disc jockey (Cullen Douglas) and dislodging The Platters single "My Prayer", he repeatedly broadcasts the words: "This is the water and this is the well.
During the broadcast, numerous listeners fall unconscious, including the young girl, through whose room's open window the creature enters and climbs down her throat.
[citation needed] Of the writing of this episode, Frost said: The idea, obviously—or, well, not obviously—was that we'd never done anything close to what you might describe as a Twin Peaks origin story, [showing] where this pervasive sense of darkness and evil had come from.
He ran with it and elevated it to a whole other level [...] the atomic explosion was probably half a page as written, but I knew that, in David's hands, it could run as long as 10 or 12 minutes, and it would be riveting.
[...] When I got off the train I stepped into this soft dust that was like eight inches deep and it was blowing, and out of the earth these huge moths, like frogs, were leaping up, and they'd fly and flip and go back down again.
[10] The page (numbered 195) translates on-screen to the woodsman breaking inside the radio station: differently from the final cut, the spelling of the episode's titular line was "Got a light?"
and the woodsman was supposed to "speak disturbing, atonal word-like mechanical sounds into the mic, going out over the air in a strange monotone", part of which composed the mantra that was performed in the final episode.
On set, Lynch showed Joy Nash how to hold the Laura Palmer orb, kissing it and giving it "so much love" before letting it go; he also demonstrated to her how to walk through the theatre, with bouncing steps like a "little cherub.
During the scene in which Monroe shoots Cooper's doppelgänger, a severely slowed-down recording of Ludwig van Beethoven's Moonlight Sonata (1801) is used.
[18] Two original recordings were used in the course of the episode, during the scenes in the structure over the purple sea: "Slow '30s Room", a remixed excerpt of the seventh movement in Lynch and Dean Hurley's album The Air Is on Fire (2007), and "The Fireman" by Angelo Badalamenti; both were eventually released on the September 2017 soundtrack album Twin Peaks: Limited Event Series Original Soundtrack.
The critical consensus reads, "'Part 8' adds yet another masterful chapter to Twin Peaks' return—and arguably one of the finest hours of creator David Lynch's incredible career.