Darth Vader (Anakin Skywalker) is a fictional character in the Star Wars franchise. He is a major antagonist in the original trilogy, but as Skywalker, is the main protagonist of the prequel trilogy. In the third film of the prequel trilogy, he becomes the secondary antagonist (following his rebirth as Darth Vader) alongside Palpatine. Star Wars' creator George Lucas has collectively referred to the first six episodic films of the franchise as "the tragedy of Darth Vader".

Originally a Jedi prophesied to bring balance to the Force, Anakin Skywalker is lured to the dark side of the Force by the evil Palpatine, who manipulates his wavering faith towards the Jedi and his fear of possibly losing his secret wife Padmé Amidala and becomes a Sith Lord. After fighting a lightsaber battle with his former mentor Obi-Wan Kenobi in which he is severely burnt and dismembered, Vader is transformed into a cyborg. He then serves the Galactic Empire as the villainous Darth Vader until he redeems himself by saving his son, Luke Skywalker, and seemingly killing Palpatine, sacrificing his own life in the process. He is also the father of Princess Leia, and grandfather of Kylo Ren, the main antagonist of the sequel trilogy.

The character has been portrayed by numerous actors, David Prowse physically portrayed Vader while James Earl Jones voiced him in the original trilogy, Sebastian Shaw portrayed the unmasked Vader in the sixth film as well as the character's force ghost in the original release of it. Jake Lloyd and Hayden Christensen played the character in the prequel trilogy in the first and next two films respectively with Christensen also portraying the character's force ghost in the re-release of the sixth film in 2004. His cinematic appearances span the first six Star Wars films, as well as Rogue One, and he is referenced in both The Force Awakens and The Last Jedi. He also appears in television series (most substantially The Clone Wars) and numerous iterations of the Star Wars Expanded Universe, including video games, novels, and comic books.

Darth Vader has become one of the most iconic villains in popular culture, and has been listed among the greatest villains and fictional characters ever. The American Film Institute listed him as the third greatest movie villain in cinema history on 100 Years... 100 Heroes and Villains, behind Hannibal Lecter and Norman Bates. His role as a tragic hero in the prequel trilogy was also met with positive reviews.