A chance discovery by a probe droid reveals the Rebel Alliance's main base on the planet Hoth. Darth Vader prepares for a surprise long-range attack - but his plans are ruined when Admiral Kendal Ozzel leaves hyperspace near the planet - setting off the Rebels' early-warning sensors. Vader then launches a ground attack with a powerful onslaught of Snowtroopers and AT-ST Walkers. The Rebels target their laser turrets at the invading Imperials - and Luke bravely leads his fellow Rebels into battle with the formidable walkers. But the Alliance is outnumbered and outgunned - and the order is given to retreat. The Rebels succeed in fleeing the planet - giving the Empire a cold and bittersweet victory.