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The X-Files 6x13

Agua Mala

Arthur Dales summons Mulder and Scully to his holiday home in Florida where he is concerned over the disappearance of his neighbors. Despite the raging hurricane, Mulder and Scully head out to investigate and discover several strange deaths caused by an octopus-like sea creature that swam in through the overflowing sewer system.

The X-Files: S06E13
Feb. 21, 1999

The X-Files season 6