Source: The Empire Strikes Back
Han, Leia, Chewie, and the droids escape from Darth Vader by hiding the Millennium Falcon among the garbage that's periodically jettisoned by the Imperial fleet. To stay out of Vader's way, Han heads to Bespin, where his old smuggling buddy Lando Calrissian now runs a mining colony. They arrive at Cloud City, where Lando tells them he just made a deal that'll keep the Empire out of Bespin forever. Calrissian opens a door – and there is Darth Vader, with Boba Fett beside him. Han's "friend" has delivered them into the hands of the Empire.
