Open Water is a 2003 drama psychological horror film loosely based on the true story of an American couple, Tom and Eileen Lonergan, who in 1998 went out with a scuba diving group, Outer Edge Dive Company, on the Great Barrier Reef, and were accidentally left behind because the dive-boat crew failed to take an accurate headcount. In 2006, a film was marketed as a sequel entitled Open Water 2: Adrift, although its plot is unrelated to the original Open Water. A third film in the series was released in 2017, entitled Open Water 3: Cage Dive, following the first film's plot of being a survival shark film, although again unrelated in continuity.