Supernatural (TV series)/Recap/S01/E04 Phantom Traveller

Season 1, Episode 4:

Phantom Traveler
Dean and Sam track down and attempt to exorcise a demon that's causing plane crashes.

Tropes
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 * Audible Sharpness: A metallic sound is heard when Dean removes his knife from under his (presumably soft and cushy) pillow.
 * Black Eyes of Evil: The demon.
 * Canis Latinicus / Ancient Grome: Christo is not Latin for "God" but Greek for "The Anointed One" (as in the title "Christ"). Moreover, it should be "Christus" or "Christe".
 * Death in The Clouds: A demon's been causing plane crashes and the brothers have to find out who it's possessing and exorcise it, before it crashes another plane. Unfortunately, they don't manage to stop it getting on the plane, so the climax takes place on a plane.
 * Demonic Possession
 * Leave No Survivors: The stated goal of the demon.
 * Super Smoke: The demon, when he's not possessing someone. Apparently, even in this form it can threaten a plane to crash.
 * Villains Never Lie: Before being exorcised, the demon claims knowing what happened to Jessica. Dean tries to reassure Sam by saying that demons always lie, but...
 * Why Did It Have to Be Snakes: Dean doesn't like airplanes.