Darth Vader’s revelation that he’s Luke Skywalker’s biological father in the climactic scene of The Empire Strikes Back has been hailed as arguably the most iconic plot twist in movie history. While the spoiler-ridden prequel era and countless parodies have taken away a lot of its impact for modern viewers, audiences back in 1980 were blown away (as satirized by The Simpsons).

All the best plot twists seem obvious on rewatches of the movie, because a filmmaker with their eye on the ball will carefully foreshadow it in the build-up. In The Prestige, Christopher Nolan indirectly explains the twist to the audience via the birdcage trick. In The Departed, Martin Scorsese marks characters for death with an “X” duct-taped near their head. In Fight Club, David Fincher uses all kinds of editing tricks to hint at Tyler Durden’s true nature. This is also true of Empire, which drops a few hints about Vader’s connection to Luke in the lead up to the big reveal.

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Widely regarded as the greatest Star Wars movie of them all (although the 1977 original set an incredibly high bar), The Empire Strikes Back has a handful of iconic moments, like Yoda lifting Luke’s X-wing from the swamp with the Force or Leia telling Han, “I love you,” and Han replying, “I know,” right before being frozen in carbonite and sent to an uncertain future hanging on Jabba the Hutt’s wall. But the “I am your father” twist is undeniably the biggest, boldest, most memorable moment in the whole movie.

Darth Vader without his mask in The Empire Strikes Back

The first and second acts of the movie subtly foreshadow the third-act rug-pull. When an admiral catches a glimpse of Vader’s helmet being lowered onto his scarred head through a crack in the door of his medical pod, it reinforces the idea that there’s a human being under the mask. The ruthless dictator who’s been magically strangling his underlings throughout the movie is actually a person. After the first Star Wars movie had introduced Vader as a faceless embodiment of evil, the second one went out of its way to humanize him before revealing he has kids.

The fact that “vader” is the Dutch word for “father” – and the German word for “father,” “vater,” is very similar – has been interpreted as a subtle hint that Vader is Luke’s father. However, this has been debunked by the release of early script drafts that assign the name “Darth Vader” to a different character, an Imperial general. Still, it’s a neat little detail, even if it was unintentional.

Not all of Empire’s foreshadowing is subtle, of course. While Luke is training with Yoda on Dagobah, he’s drawn into a mysterious cave where he experiences a disturbing Force vision. Luke hallucinates a confrontation with Vader in which he manages to decapitate him. But when he looks down at the infamous Sith Lord’s severed head on the ground (this is easily the darkest Star Wars movie), Vader’s mask falls off and Luke sees his own face underneath it. Without knowing Vader is Luke’s father, there are a number of ways to interpret this. It could be a hint that Luke is susceptible to turning to the dark side, like his all-black clothes in Return of the Jedi were intended to suggest. But, knowing the twist that’s coming, it seems to pretty clearly telegraph that Vader is a Skywalker.

When Luke senses that Han and Leia are in trouble on Bespin and decides to cut his Jedi training short to save them, Yoda warns him against leaving. He promises to return and complete his training, but Yoda insists he’s not ready to face Vader. Of course, the wise old Jedi turns out to be right. Not only does Luke find himself hopelessly outmatched by Vader physically; he’s not prepared for the emotional toll of learning that Vader is his father.

Luke's Force vision in The Empire Strikes Back

The “I am your father” twist is one of the main contributing factors – along with Han’s unsettling fate – in The Empire Strikes Back’s groundbreaking downbeat ending. The bad guys winning in a big blockbuster sequel like Star Wars 2 (as it was known back then) was unheard of back in 1980. Empire’s downer ending was as shocking as Alfred Hitchcock’s Psycho killing off an A-list movie star at the midpoint.

While contemporary moviegoers were shocked by Empire’s twist, some fans thought that Vader might be lying, so Lucas included the scene in Return of the Jedi in which the more trustworthy (or so we thought) Obi-Wan confirms that Vader is indeed Luke’s father and that, from a certain point of view, his blatant lies about what happened to Luke’s father were true. This echoes The Last Jedi’s own twist reveal. After The Force Awakens needlessly turned Rey’s parentage into a big deal, Star Wars fans rejected Kylo Ren’s revelation that her parents are “nobodies” in The Last Jedi and assumed he was lying.

Instead of including a scene that clarified the twist like Return of the Jedi, The Rise of Skywalker confirmed this fan theory and turned Rey into a Palpatine, creating all kinds of plot holes. With the current state of the franchise’s big-screen output, it’s fair to say that Star Wars won’t be topping the shock factor of “I am your father” any time soon. Then again, it’s possible that no movie, Star Wars or otherwise, will ever top Empire’s twist.

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