Got this from a reliable source:
In Corellia, Han (Alden Ehrenreich) and Qira (Emilia Clarke) steal a fuel pod to bribe their way into an Imperial transport and escape from mobsters to whom they are indebted. Qira is captured, and Han is forced to enlist in the Imperial Academy to escape. He is determined to return to Corellia to rescue Qira. The recruiter names him Han Solo.
Three years later, Han is stationed in Mimban, where he meets a group of criminals led by Tobias Beckett (Woody Harrelson), who are masquerading as Imperial officers to steal fuel pods. Han wants to join them, but they frame him for attempted desertion, and he is arrested. In prison, Han befriends Chewbacca and they escape together and are recruited by Beckett.
Beckett and his crew attempt to steal the fuel pods from a train, but are ambushed by Enfys Nest and the Cloud Riders. Everyone dies aside from Han, Chewbacca and Beckett, and Han loses the fuel pods. Beckett is indebted to a gangster from Tatooine and approaches Corellian mobster Dryden Vos (Paul Bettany) for a loan. Vos agrees in exchange for Beckett stealing the unstable fuel source from Kessel. Han reunites with Qira, who is now Vos lover. She joins the crew as Vos representative.
Han meets smuggler Lando Calrissian (Donald Glover) and his droid companion L3-37 (Phoebe Waller Bridge), and gambles with Lando for the Millennium Falcon. Lando wins by cheating, but later joins the crew in exchange for a cut of Vos profits. They reach Kessel by performing the perilous Kessel Run, and retrieve the fuel source from Empire-controlled underground mines, filled with enslaved Wookies and droids. Chewbacca and L3-37 lead an uprising, resulting in a massive shootout with Imperial forces, during which L3-37 is destroyed and Lando is injured. Han and Chewbacca pilot with Millennium Falcon, performing the Kessel Run in 12 parsecs, and escape from the Empire.
The crew goes to a refinery in Saraven to process the fuel source into fuel pods, where they are once again confronted by the Cloud Riders. Lando escapes in the Millennium Falcon. The Cloud Riders are freedom fighters who want to prevent the fuel from falling into the hands of the organized crime. Han and Qira sympathize with them and conspire to deliver fake fuel pods to Vos. Beckett fakes his death and leaves.
Han and Qira reunite with Vos, only to learn that Beckett has betrayed them and informed Vos of their plan in exchange for the money. Beckett escapes, while Han and Qira kill Vos and his men. Han chases Beckett back to Saraven, but Qira refuses to follow him because she has done too much to go back. After he leaves, she reports to her real employer - Darth Maul.
In Saraven, Han and Beckett get into a standoff. Han shoots first, killing Beckett. Han leaves the fuel with the Cloud Riders, who give them to the Rebel Alliance. He then tracks down Lando and challenges him to a rematch. Han steals Landos cheat card and wins the Millennium Falcon in a fair game. Han and Chewbacca then decide to go to Tatooine to meet the gangster that Beckett was indebted to, who has a job offer for them.