"The Dark Phoenix Saga" is an extended X-Men storyline in the fictional Marvel Comics Universe, focusing on Jean Grey and the Phoenix Force, ending in Grey's apparent death. It was written by Chris Claremont with art by Dave Cockrum and John Byrne.
It is sometimes divided into two parts, with the Phoenix Saga (X-Men [vol. 1] #101-108, 1976–1977) referring to Grey's seeming assumption of the power and repair of the M'Kraan Crystal, and the Dark Phoenix Saga (X-Men [vol. 1] #129-138, 1980) to her corruption and fall. It is one of the most well-known and heavily referenced stories in mainstream American superhero comics, and widely considered a classic.
It was adapted for the X-Men animated series, and alluded to in the movie X2: X-Men United. A third movie, X-Men: The Last Stand, released in 2006, contains some elements from the saga. Wolverine and the X-Men adapted the Dark Phoenix Saga at the end of its first season, changing many things to make it a fresh and new version.