Hell House - S1-E17
Corrected entry: In the scene where Sam and Dean are getting coffee [right after Dean puts the itching powder in Sam's underwear], as the boy behind the counter hands Dean the coffee cup you can hear him say, "Here you go, Jensen. Jensen is actually the first name of the actor who plays Dean, 'Jensen Ackles'.
Correction: If you listen carefully, the man actually says "Here you go, gents." It says 'gents' in the subtitles too.
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