"Arcadia" is the fifteenth episode of the sixth season of the American science fiction television series The X-Files. It premiered on the Fox network on March 7, 1999. The episode was written by Daniel Arkin and directed by Michael Watkins. The episode is a "Monster-of-the-Week" story, unconnected to the series' wider mythology. "Arcadia" earned a Nielsen household rating of 10.5, being watched by 17.91 million people in its initial broadcast. The episode received mostly positive critical reception, with many reviewers praising the episode's humor.