Via Starwars.com:

IN THE FILM THAT CHANGED STAR WARS FOREVER, THEMES DEEPENED AND DARKENED.
Studying Skywalkers is an exclusive column that investigates the characters, themes, and lessons of Star Wars from an educational, literary perspective. In this installment, StarWars.com looks at themes in Star Wars: The Empire Strikes Back.

Star Wars.com continues to look at themes present in the six existing Star Wars films as we get closer to Star Wars: The Force Awakens. Up next on our list is The Empire Strikes Back. Routinely analyzed and dissected for incredible action, evolving character dynamics, and, of course, the stunning reveal of Skywalker pedigree. The penultimate film in the original trilogy contains themes that heighten personal cost to each character, and adds more layers of complexity and drama to the Star Wars saga. As with many good stories, the film provides more questions than answers, and has left a legacy on popular culture for many generations of not only Star Wars fans, but filmgoers as well.

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