Lost: Dave

"Dave" is the 43rd episode of Lost and the 18th episode of the second season. The episode was directed by Jack Bender, and written by Edward Kitsis and Adam Horowitz. It first aired on April 5, 2006, on ABC. In flashbacks, Hugo "Hurley" Reyes is in a mental institution, where he deals with an imaginary friend, Dave. Libby also has a brief flashback in this episode, revealing that she attended the institution along with Hurley. The island events in the present day have Hurley seeing Dave on the island, while other survivors confront "Henry Gale" (Michael Emerson) after his stated backstory is revealed to be false. The episode addresses a fan theory which considered the events of the series to be hallucinations or dreams. The character of Dave was written as both a side of Hurley who denied his problems and an analogue to Hurley's disappeared father, and his scenes were filmed so that his reveal as imaginary would be a plot twist.