As established, Anakin Skywalker, who would become Darth Vader, had two children that were separated from him at birth. He never figures out explicitly that Princess Leia is his daughter, even while he tortures and captures her, but does he know that Luke Skywalker is his son all through the Star Wars movies?
Does Darth Vader know Luke is his son all throughout? Surprisingly, we don’t see evidence of Darth Vader immediately figuring out that Luke Skywalker is his son. From the original movie, Vader seems to disregard any family connection and views Luke as the weaker enemy. It does take him a few years but Vader does catch on.
In the next film, The Empire Strikes Back, Darth Vader not only finds a vested interest in Luke Skywalker as more than someone powerful in the Force but a family connection that Vader can try to convince to come to join him in the Dark Side. He manipulates Luke’s understanding of the galaxy, setting him up in a complicated dilemma of life and death.
How Does Darth Vader Find Out Luke is His Son?
After the Empire’s defeat and destruction of the Death Star in A New Hope, Darth Vader must recollect and try to find ways to bring strength back to the Empire. Vader and his spies come back together after the Battle of Yavin to discover dirt against the Rebel Alliance, especially against Luke Skywalker.
Star Wars experts could argue that Luke’s last name was the easy giveaway all along. Since Luke kept the name Skywalker, Darth Vader still recalls a time where he was Anakin Skywalker before he turned to the Dark Side himself. Seeing Luke as a direct threat to the Empire, Vader focuses all his attention on him.
The concrete evidence comes from an interaction between Vader and Emperor Palpitate in The Empire Strikes Back, as the Emperor says a ‘great disturbance in the Force’ reveals Luke as the new public enemy of the galaxy. Vader initially brushes it off, citing his youth as a lack of threat. However, Vader comes around to the idea of turning the new enemy, Luke, to the Dark Side because “he would make a great asset.”
Why Is Darth Vader Obsessed With Luke?
Aside from discovering Luke is Vader’s son, it’s important to look at the complex dynamic between Vader and Luke that gets developed in the original trilogy. Luke and Vader first become connected as Leia is captured by Vader for her role in contacting Obi-Wan Kenobi, and Leia asks for Luke’s help along with his team, including Han Solo, Chewbacca, and C3-PO.
As Vader kills Obi-Wan, Luke, Leia and Han Solo escape, despite Vader’s tracking device on their ship that allowed the Empire to discover the secret base set up by the Rebel Alliance. Vader’s obsession really begins because of the Death Star’s inability to stop the Rebel Alliance, as Luke leads a critical attack on Vader aboard the Millennium Falcon. The Empire’s station was destroyed, but Vader survives the attack, although Luke took the victory.
The official Star Wars website goes into great detail about why Vader became set on finding and destroying Luke while discovering the family connection they both share. Vader sets up droids all over the galaxy to find Rebel bases in search of Luke. Once again, Luke and the rest of the Alliance manage to escape. While pursuing Luke, Vader discovers through his spies, namely Boba Fett and Emperor Palpitate that Luke Skywalker is Vader’s son, giving Vader a new purpose for hunting down Luke.
While Luke, Leia, and Han find solace on Cloud City, Boba Fett put together a trap behind the scenes that led the trio to face Darth Vader. As Han Solo gets tortured the second time around, Luke sacrifices his first round of Jedi training from Yoda to save his friends. Vader knows that Luke is a weaker Jedi than he is, so his planning of finding Luke and defeating him presents Vader with a big advantage.
The first time Luke and Vader battle showcase Vader’s ultimate power of the Dark Side onto Luke. It creates an imbalanced power dynamic between father and son. Instead of a tender moment where Vader reveals Luke’s true parental upbringing, the news that Vader is Luke’s father is presented with malice and an ulterior motive — to bring Luke to the Dark Side.
Needing to Bring Luke to the Dark Side
Because Luke had defeated the Empire once before, Vader knows that the Empire is not the strongest establishment in the galaxy, even with their strong intuition with the Force. During The Empire Strikes Back, Luke is characterized as a naive, easily influenced, and emotional Jedi in training, as he takes the news of Vader being his father with anger and fear. Luke goes against Vader by turning down his offer of the Dark Side.
None of this stops Vader from bringing his son to the Dark Side. However, now that Luke knows that Vader is his father, the young hero’s motivations change very quickly in The Return of the Jedi. While Vader supervises the construction of Death Star 2.0, Luke holds onto faith that his father hasn’t gone completely evil, and seeks to bring him out of the Dark Side.
As it would turn out, Vader’s saturation into evil and the Dark Side was irreversible, as Yoda and Obi-Wan warned Luke that Vader had to be defeated to bring peace back into the galaxy. Luke figures out Vader’s obsession and true intentions to himself, leading to another intense fight.
In a sense, Vader’s obsession with Luke was worthwhile, since he did convince Luke to give in to his feelings of hate, anger, and fear when battling each other. Because these feelings arose, Luke cuts off Vader’s hand and almost kills him on the spot. However, Vader’s obsession with Luke also stems from wanting a connection with his long lost son.
This connection shows itself as the Emperor taunts Luke to kill his father and take his place as the new Sith Lord of the Dark Side. Once again, Luke refuses and then is subject to torture that Vader has to witness. While Vader dies saving Luke from torture and killing the Emperor, the last moments of true compassion for Luke justify Vader’s obsession with him all along.
Conclusion: Vader’s Relationship With Luke and Leia
While many Star Wars fans point out the storyline of Luke and Leia being siblings and descendants of Darth Vader is flawed, it also makes for interesting storytelling. Without it, Luke has no motivation to face Vader and become the next big Jedi.
There was also no way Luke and Leia could be immediately discovered as the children of Darth Vader by Vader himself early on. Setting up the characters as members of the Rebel Alliance versus the Empire makes the original Star Wars movie easy to follow. Throwing in the twist of Luke Skywalker as the son of Darth Vader in The Empire Strikes Back creates an interesting conflict.
Leia had no reason to know that Vader was her father, other than to discover her capabilities as a potential Jedi. She was not happy to discover that she was the daughter of the leader of the Dark Side, but it led her to be trained by her brother Luke as a Jedi, strengthing her role as Senator and as Princess.
Vader’s unawareness of Leia as his daughter, but knowing that Luke was his son makes no sense in the story, but it does tie the prequels and the original trilogy together, just like George Lucas wanted to do.