"The Clash of Lightsabers" is the tenth and final episode of The Empire Strikes Back radio drama. It first aired on National Public Radio on April 11, 1983. The episode adapts the climax and ending of , including Luke Skywalker's duel on Cloud City against Darth Vader and his escape from the planet Bespin.
A firefight intensifies as ever more Stormtroopers move in against the band of Rebels. After some moments of struggle, Artoo-Detoo manages to get the doors open. To cover their escape across the open landing platform, Artoo uses his fire extinguisher to create a smokescreen. All five manage to board the Falcon, but even Leia acknowledges that they have no way to go back for Luke.
Deep inside Cloud City, Vader appears to Luke. To demonstrate his command of the Force, Vader mentally lifts numerous objects and hurls them at him, then summons a strong wind that pulls him into a reactor shaft. Meanwhile the Millennium Falcon takes off under fire.
Luke tells Vader that he is going to jump.
Far down in the shaft, Luke has managed to land safely on a gantry, but Vader finds him and points out the great distance left to fall. Luke keeps fighting, once glancing Vader with his lightsaber blade, until Vader counterattacks and slices off his sword hand. Vader, desperate to avoid killing Luke, repeatedly asks Luke to join with him in the Dark Side of the Force. When Luke does not relent, Vader finally tells him the horrifying truth: "I am your father." Vader makes a final plea that together he and Luke can destroy the Emperor and rule the Galaxy together. Luke instead jumps into the shaft, choosing suicide over giving Vader what he wants.
But Luke survives. In desperation he cries out first to Ben Kenobi, then to Leia. Aboard the Falcon, Leia receives his message telepathically and suddenly knows where Luke is. Chewbacca believes her, and the Falcon turns around despite the imperial TIE fighters that are in pursuit. Leia locates Luke beneath Cloud City hanging from a vane. Chewie maneuvers the ship carefully so that Lando can open an airlock and pull Luke aboard. Then the ship races away.
Once the Millennium Falcon is out of Bespin's gravity field, Chewbacca initiates the jump to lightspeed only to find that the hyperdrive still does not work, despite Lando's order that it get fixed. Luke and Vader communicate telepathically, calling to each other as "Father" and "Son." Vader again exhorts Luke to join him. Elsewhere in the Falcon, Artoo tells Threepio that the hyperdrive had been sabotaged, having learned this from the city's computer. Artoo pauses his work reassembling Threepio and performs a quick repair to the starship. At long last, the Falcon jumps to lightspeed.
Some time later, Luke is again under the care of the medical droid Too-Onebee, who is fitting him with a new prosthetic hand. Lando and Chewbacca arrive to say goodbye; they are going to Tatooine to find Han Solo. Luke will meet them later with the droids. Lando and the droids have a newfound appreciation for one another: Lando says that they are welcome to ship with him any time, while Threepio calls Lando "Captain Calrissian" with obvious respect and affection. Lando promises Leia that he will bring Han back to her. Luke's hand completed, he joins Leia and the droids to watch the Falcon take off while they all prepare themselves for their next mission.
"The Clash of Lightsabers" is very close to the corresponding scenes in the film , with only a few minor differences in pacing and interpretation. When a blast of wind blows Luke into the reactor shaft, the radio episode specifies that Vader created the wind with the Force, while in the film this is ambiguous. At the climax of the duel, Darth Vader is characterized as desperate in his desire to finally compel Luke to join with him. Panic rises in his voice when Luke threatens to jump.
- The Empire Strikes Back: The National Public Radio Dramatization