Jar Jar Binks first appears in The Phantom Menace as a bumbling Gungan from the planet Naboo. After his tribe banishes him for his clumsiness, he is nearly killed by a federation transport, only to be saved at the last minute by Jedi Master Qui-Gon Jinn (Liam Neeson) and his padawan Obi-Wan Kenobi (Ewan McGregor). The Jedi persuade Jar Jar's tribe to release him to their custody as a guide. He later goes with the Jedi and Queen Padmé Amidala (Natalie Portman) to the planet Tatooine, where he meets and befriends Anakin Skywalker (Jake Lloyd).
Jar Jar later appears in the film's climactic battle scene, where he leads his fellow Gungans in defeating the evil Trade Federation. For his heroics, he is made a general in the Gungan army, and Padmé gives him a ceremonial medal.
Jar Jar's role in Attack of the Clones is much smaller, but his actions are significant. Ten years after helping to save his planet, he is a delegate to the Galactic Senate, and as such plays a role in bringing his old friends Obi-Wan and Anakin (Hayden Christensen) back to Coruscant, where he greets them with enthusiasm. Later, on the behalf of Naboo and the Jedi, he gives a speech to the assembled Senate in favor of granting Chancellor Palpatine (Ian McDiarmid) vast emergency powers (and arguably starting the wheel that led to the Clone Wars, Galactic Empire, Galactic Civil War, and all the deaths therein.)
He appears in only one scene in Revenge of the Sith