Passage: The story begins immediately after the last scene of The Force Awakens. Johnson had his story group watch films such as Twelve O'Clock High, The Bridge on the River Kwai, Gunga Din, Three Outlaw Samurai, Sahara, and Letter Never Sent for inspiration while developing ideas. He felt it was difficult to work on the film while The Force Awakens was being finished.In December 2015, Lucasfilm president Kathleen Kennedy said, "we haven't mapped out every single detail [of the sequel trilogy] yet", and that Abrams was collaborating with Johnson and that Johnson would in turn work with (then) Episode IX director Colin Trevorrow to ensure a smooth transition. Abrams is an executive producer along with Jason McGatlin and Tom Karnowski. Lucasfilm announced the film's title, Star Wars: The Last Jedi, on January 23, 2017.During production, Hamill expressed disagreement with the direction his character was taken, finding the character's more disillusioned status to be contradictory to his previous optimism. Hamill later said that he regretted making his initial misgivings public and compared his disagreements to clashes he had with George Lucas during the filming of Return of the Jedi.

Question: Why did Johnson show various films?
inspiration while developing ideas