Discovered by one of Darth Vader's probe droids, the Rebel Base on Hoth faces invasion by a landing force deployed from Imperial Fleet star destroyers. Echo Base is protected by a powerful energy shield, but this defense can do nothing to stop ground units from advancing.
Under the command of the capable General Veers, the Imperial Blizzard Force marches on the Rebel base, unleashing fearsome AT-AT walkers and legions of snow troopers. The Rebels' General Carlist Rieekan oversees a hurried retreat as Commander Luke Skywalker leads the Rogue Squadron of snowspeeders in a delaying action against the dreaded Imperial forces.
Rebel losses are devastating and the snow trenches and defensive emplacements are smashed disastrously by the almost-unstoppable Imperial walkers. Behind the shelter of the mountain housing Echo Base, Rebel transports are desperately loaded and dispatched into space, carrying evacuated Rebel personnel and material as Echo Base collapses in ruin under the press of Imperial occupation.