This is the plot of Episode IV: A New Hope.
The movie fades in on two droids. They are our main characters until they land safely on Tatooine. There we meet th true protagonist, Luke.
Luke is a simple farm boy who longs for adventure. He finds a distress message from a princess in R2D2. The message eventually leads him to a powerful Jedi named Obi-Wan Kenobi. Obi-Wan asks Luke to join him in rebelling against the evil Empire.
After the Empire kills his family, Luke decides to join Obi-Wan on a quest to help the princess and the Rebellion destroy the Empire/ He leaves Tatooine with Obi-Wan, the droids, Han Solo, and Chewbacca.
Luke begins to learn the ways of the Force. Their ship, however, is captured by the Empire's Death Star. They infiltrate a major control room and plan their escape.
They discover that the princess who sent the distress message (Princess Leia) is being held abord the Death Star. They release her from her cell.
Obi-Wan sacrifices himself, creating a distraction that allows the party to escape the Death Star
They succesfully fight off an attack on the ship, and return to the Rebellion encampment to plot their attack on the Death Star.
With the help of his new friends, Luke uses the ways of the Force and successfully destroys the Death Star.