The Empire Strikes Back
Lando Calrissian first appears in as the administrator of Cloud City, concerned primarily with keeping the Galactic Civil War and the Empire out of his affairs. One day, Darth Vader arrives and blackmails Calrissian to betray his old friend Han Solo over to the bounty hunter Boba Fett by threatening to take over the city. Unwilling to leave the city in the hands of the Empire, Calrissian reluctantly does so, but his conscience gets the better of him when Vader goes back on his word and takes Leia Organa and Chewbacca as prisoners. In the ensuing evacuation of Cloud City, he helps Leia, Chewbacca, R2-D2 and C-3PO escape. He then assists Leia in rescuing the maimed Luke Skywalker from the underside of Cloud City. Afterwards, he joins the Rebel Alliance and promises Leia he will find Han.
Return of the Jedi
Calrissian later goes undercover to help Luke Skywalker rescue Solo from Jabba the Hutt. During a heated battle with Jabba's henchmen, Han saves Calrissian from being devoured by a Sarlaac; in return, Calrissian helps Han and his friends destroy Jabba's barge. For his heroics, he is made a general in the Rebel Alliance. He then takes the pilot chair in the Millennium Falcon, which was originally his, and leads the attack on the second Death Star. He leads the Rebels to victory by destroying the gigantic battle station and, with it, the Empire.