Luke Skywalker and R2-D2 headed to Thaldo to warn the planet's Rebel outpost about an upcoming Imperial attack. On Thaldo, Luke liberated a Rebel prisoner from Imperial custody, who gave him an ID card that would allow him access to the base.
Luke discovered a small outpost staffed by a Rebel officer, who escorted him to the main base about a T-47 airspeeder. Luke was too late to warn the base—the Imperial attack began just as he arrived. After fighting off the initial wave, Luke managed to repair the base's ion cannon, allowing the Rebels stationed on Thaldo to escape the planet.