The film opens with the familiar preface: "A long time ago in a galaxy far, far away..." A scrolling roll-up disappears into infinity in the stars as it describes the time-period:

It is a dark time for the Rebellion. Although the Death Star has been destroyed, Imperial troops have driven the Rebel forces from their hidden base and pursued them across the galaxy. Evading the dreaded Imperial Starfleet, a group of freedom fighters led by Luke Skywalker has established a new secret base on the remote ice world of Hoth. The evil lord Darth Vader, obsessed with finding young Skywalker, has dispatched thousands of remote probes into the far reaches of space...

With the destruction of the Death Star, heroic Luke Skywalker (Mark Hamill), with the help of the mysterious Force, has joined with the other surviving Rebels to escape the Empire's wrath, with Princess Leia (Carrie Fisher) and other freedom fighters, on the bleak and frigid planet of Hoth. Probe droids were dispatched by Darth Vader to locate the hidden rebels. One of the many remote probes crash-lands on the desolate icy and frozen world of Hoth, and then rises up out of its crater to begin its search by floating across the ice plain. As Luke rides across the same cold and lonely ice plain of Hoth on his Tauntaun (snow lizard), he sees an object, thinking it might be a meteorite, drop from the sky through his pair of electro-binoculars. He sends a com-link message to Han Solo (Harrison Ford), reporting that he hasn't picked up any "life-readings" -- Han jokes back: "There isn't enough life on this ice cube to fill a star cruiser." But Luke plans on checking out the meteorite. As he steadies his beast, he turns to see a monstrous Wampa snow creature (Des Webb) towering over him - a big white claw swats him and he is knocked unconscious. His mount is killed and he is then dragged across the ice.

The hidden Rebel base is located in a large ice cave, where Han Solo has just returned from his own scouting expedition. His Wookiee co-pilot Chewbacca ("Chewie") (Peter Mayhew) is making welding repairs to the lifters of their damaged freighter ship The Millennium Falcon. In the Command Center, Han finds the Rebel Force General Rieekan (Bruce Boa), and reports on his mission, and then explains that he is now forced to leave - to pay off a debt from a previous smuggling operation, with bounty hunters on his trail:

There's a price on my head. If I don't pay off Jabba the Hutt, I'm a dead man.

Rieekan thanks Solo for being such a good fighter. Solo then says goodbye to the Princess, who is frosty about his sudden departure, although she follows after him in an icy, south passage corridor and tells him with a mixture of emotional and professional sentiment: "Han, we need you!...You're a great help to us. You're a natural leader." He imagines that she has feelings for him, and challenges her to give him a good-bye kiss:

Han: Afraid I was gonna leave without giving you a good-bye kiss?
Princess (retorting): I'd just as soon kiss a Wookiee.
Han: I can arrange that! You could use a good kiss!

They both storm away from each other. In the hangar, the two droids: round, beeping R2-D2 (Kenny Baker) and tall, golden C-3PO (Anthony Daniels), alert Han to the fact that Commander Luke Skywalker hasn't returned, and it's getting dark and colder: "He hasn't come back yet...Nobody knows where he is." C-3PO believes Luke is "in considerable danger." Han Solo leaps onto the back of a Tauntaun and rides out into a cold blizzard to rescue his friend. Meanwhile, Luke awakes finding himself upside down, frozen by his boots and hanging like a human stalactite from a jagged cave ceiling within an ice gorge. His face is both swollen and bloody. He hears the moaning, grumbling roar of the Wampa ice monster in the distance, and sees his own out-of-reach light-saber half-buried in the snow nearby. As he desperately tries to reach it, he concentrates and uses the Force to propel it into his hands. He ignites the sword, cuts himself loose with one slash, and confronts the hungry, white-furred Wampa looming toward him - with one swing, he amputates the right arm of the beast and then flees, stumbling into the frigidly-cold exterior. At the same time, Han is riding through the snow searching for him, but finds nothing. As the base's shield doors are about to be closed for the night, C-3PO reports that R2-D2 predicts "the chances of survival are 725 to 1." The Wookiee lets out a distressing howl.

Luke collapses into the snow, feeling the freezing cold zapping all of his strength. As his senses go numb, he hears Ben 'Obi-Wan' Kenobi (Alec Guinness) speaking before him in a faint snowy vision, instructing him to become the Rebellion's only hope:

Luke, Luke...You will go to the Dagobah system...There you will learn from Yoda, the Jedi master who instructed me.

Han locates the unconscious Luke in the snow, and rushes to his side: "Don't do this, Luke. Come on, give me a sign here." At that moment, his Tauntaun bellows and falls over dead, frozen by the cold. Solo drags the delusionary Luke to the beast's side, cuts open its belly with the light-saber, and stuffs the half-frozen Luke into the steaming carcass insides to keep him warm, and then constructs a shelter for them from supplies on the dead beast's back. The next morning after the sun rises, a fleet of snow-speeders leaves the Rebel base on a search/rescue mission, and one of the young pilots on Rogue Two locates them (Han sarcastically jokes: "Nice of you guys to drop by") and reports their sighting. The two are brought back to the base, where Luke is treated in the medical center. He is placed in a healing substance within a rejuvenation chamber-tank to heal his wounds. For saving his life again, Han reminds the recovering Luke: "That's two you owe me, junior." There is another delay in Han's plans to leave - General Rieekan believes it is simply too dangerous for any ship to leave the base until their energy field is activated.

In a consultation within the Rebel's Command Center, there are findings that a sensor is reporting a disturbance and unusual signal coming from an unidentified metal object (the Imperial probe droid) at Station 38. C-3PO surmises: "It could be an Imperial code." Solo is also suspicious: "It isn't friendly, whatever it is. Come on, Chewie, let's check it out." Out on the ice plain where the robotic device is located (and receiving instructions through its antennae), the hostile droid fires with its deadly laser ray upon Chewbacca ducking behind a snowbank as a diversion. From behind, Han blasts the droid and it explodes into many pieces, possibly from an additional self-destruct mechanism. Princess Leia knows it is an Imperial probe droid that notified the Empire of their location when it was destroyed. Rieekan orders the start of the evacuation of the Rebel base.

Light years away on the Imperial fleet on Darth Vader's (David Prowse/voice of James Earl Jones) command ship the Executor leading the way through space with Imperial Star Destroyers and TIE fighters alongside, Imperial Force Admiral Piett (Kenneth Colley) reports to angry and skeptical Admiral Ozzel (Michael Sheard) about a fragment of a signal from a probe droid in the Hoth system, a possible life-reading. The dark figure of Darth Vader strides forward and asks: "You've found something?" Vader examines the signal's image and confirms:

That's it. The rebels are there...That is the system. And I'm sure Skywalker is with them. Set your course for the Hoth system.

He then orders General Veers (Julian Glover) to prepare his men. Meanwhile, evacuation measures are being undertaken at the base, and Han makes last-minute, unsuccessful repairs to The Millennium Falcon, as sensors in the Command Center detect approaching Imperial ships: "There's a fleet of Star Destroyers coming out of hyperspace in Sector Four." General Rieekan orders rerouting of all power to the energy shields, and preparations for a ground assault.

On Vader's command ship, General Veers interrupts Darth Vader in a sealed meditation chamber with news: "Com-Scan has detected an energy field protecting an area of the sixth planet of the Hoth system. The field is strong enough to deflect any bombardment." Angered, Darth Vader knows that the rebels are alerted to their presence. He is furious that clumsy and stupid Admiral Ozzel came out of light-speed too close to the system. He orders Veers: "Prepare your troops for a surface attack." On a view-screen, Vader reprimands Ozzel and chokes him with an invisible hand. As his commander gags to death, Captain Piett is promoted to Admiral and given command of the troops, and ordered to make sure none of the Rebel fleet escape from the planet.

Meanwhile, Princess Leia briefs the Rebel pilots about their duties (X-wing fighters escorting transport ships would pass by the energy shield and proceed to a rendezvous point), while exterior ground troops prepare to defend the main generator that powers the energy shield. The first of the transport ships slip through the opened energy shield, as an ion cannon fires to protect it against hovering Imperial Star Destroyers. On the planet's surface, Luke and other pilots on Rebel snow-speeders are readied for the ground assault against gigantic, tall, four-legged, lumbering armored machines of Imperial destruction called Snow-Walkers, spitting laser-fire. Inside the lead Walker, General Veers surveys the battle and his ultimate target -- the Rebel's main generator, and promises Vader: "The shield will be down in moments." Rebel troops fight off the onslaught, but the Imperial fire-power is too great. Luke suggests using harpoons and tow cables to aim for the Walker-legs - to tangle and trip them, topple them to the ground, and then cause them to explode by aiming at the Walkers' exposed necks. Princess Leia orders evacuation of the remaining ground staff, as Han and Chewie make final repairs to their Falcon. And Veers orders his troops to prepare for a ground assault, now that they are closing in. During a pass at another Walker, Luke's craft is hit and his snow-speeder crash-lands in front of the huge feet of an approaching machine. He snatches a land-mine before his ship is crushed, runs under the Walker, fires a magnetic cable from his harpoon gun at its metal underbelly, and hoists himself up. He cuts open a hatch in the armor with his light-saber and throws the land-mine into the machine to blast it to pieces. It is the second Walker to fall - but he is left behind in the snow.

The Rebel base is taking heavy fire and is in shambles, crumbling and cracking, as everyone evacuates and the relentless Imperial troops enter, while the remaining Walkers press forward. In the devastated Command Center, Solo encourages C-3PO and Princess Leia, who called for retreat, to get to the last transport, but their way is blocked by a chunk of frozen ice. He races with her to the Falcon as the base is infiltrated by storm-troopers - followed by the ominous figure of Darth Vader. Veers watches as the Rebel's main generator is targeted and fired upon, causing it to disintegrate and eliminate the energy field. Solo, C-3PO and the Princess reach the Falcon (although the Princess has doubts: "Would it help if I got out and pushed?") and lift off from the hangar just in time, evading a laser cannon set up by the Imperial stormtroopers. Outside, Luke watches as it streaks past and flies off - he races to his own X-wing fighter awaiting him (with R2-D2) and takes off - but decides to set a new course: "We're not gonna regroup with the others. We're going to the Dagobah system." TIE fighters and two oncoming Imperial Star Destroyers are in pursuit of the Falcon, but Han is able to cleverly outmaneuver them with a steep dive, and he dodges the ships. But he is unable to activate the hyper-drive to jump to light-speed. Han notes the malfunctioning hyperdrive: "We're in trouble." He decides to enter an approaching asteroid field to evade his followers, and shrugs when Leia is disbelieving - he responds: "They'd be crazy to follow us, wouldn't they?" Although pursued by four TIE fighters, his strategy is only partially-successful - two of them are blind-sided by spinning asteroids. Han then decides to fly his freighter lower into the canyon-like depths of one of the large asteroid craters, and then takes refuge in a long cave-tunnel on the crater's far side, after the remaining two TIE fighters collide with each other in a narrow ravine.

In his fighter, Luke descends into the cloud-covered atmosphere of Dagobah, after determining it has "massive life-form readings," but no cities or technology. But he loses flight control as the scopes go dead and he lands with a jolt in a foggy, marshy bog, surrounded by huge gnarled trees. He is uninjured, but R-2 falls overboard and splashes into the water, where a swamp creature takes him under, but then spits him out onto the mossy, misty shore. Shaken, Luke has climbed out of his ship and is able to help upright R2, who complains that it was a "bad idea" to come there. Luke thinks: "It's like something out of a dream, or...maybe I'm just going crazy."

On board Vader's command ship the Executor, Admiral Piett approaches Vader's meditation chamber and catches a brief glimpse of the back of the Dark Lord's scarred head, as his helmet is put into place. He reports a sighting of the Millennium Falcon in the asteroid field, but Vader is unperturbed: "Asteroids do not concern me, Admiral. I want that ship, not excuses." Vader is certain that the crew of the Falcon is still alive. He orders continued sweeping of the asteroid field until they are found. Luke retrieves supplies from his downed, half-submerged X-wing fighter, and then in a clearing of dry ground, Luke sets up camp, powers up R2-D2, and then mutters:

Now, all I've gotta do is find this Yoda, if he even exists. It's really a strange place to find a Jedi master. This place gives me the creeps. Still, there's something familiar about this place.

Feeling like he is being watched from the dark trees, he suddenly whirls around to face an odd, dwarfish creature about two feet tall, dressed in rags. The little but aged, wizened, greenish fellow has large bright eyes and pointy ears, and assures Luke who has a blaster in his hand: "I mean you no harm." Luke explains how he is looking for "a great warrior" -- the creature scampers down into Luke's food supply, makes a mess of his equipment, and tries to steal a tiny glowing power lamp or rod, after he replies: "Wars not make one great." When Luke specifies: "I'm looking for a Jedi master," the impish dwarf's eyes light up, and he proposes taking Luke into the fog to seek Yoda:

Oh, Jedi master. Yoda. You seek Yoda...Take you to him I will. Yes, yes, but now we must eat. Come! Good food. Come!

Back on the Falcon, they soon find themselves in an unstable environment, with a malfunctioning hyperdrive. Han seeks out C-3PO's advice on how to repair the Falcon's hyperdrive, and learns the negative power coupling needs replacement. Solo finds Leia trying to help by opening a stuck energy valve. She admits he is all right when he doesn't spitefully call her "Your Worship," or act like a "scoundrel." Han tells her that he likes the sound of that epithet, and claims that he is a "nice man" - who deserves a kiss, although she mildly protests but reciprocates after he coaxes her:

Han: Hey, Your Worship, I'm only trying to help.
Princess: Would you please stop calling me that?
Han: Sure, Leia.
Princess: You make it so difficult sometimes.
Han: I do, I really do. You could be a little nicer, though. Come on, admit it. Sometimes you think I'm all right.
Princess: Occasionally, maybe, when you aren't acting like a scoundrel.
Han: Scoundrel? Scoundrel? I like the sound of that. (He rubs her hand)
Princess: Stop that.
Han: Stop what?
Princess: Stop that. My hands are dirty.
Han: My hands are dirty, too. What are you afraid of?
Princess: Afraid?
Han: You're trembling.
Princess: I'm not trembling.
Han: You like me because I'm a scoundrel. There aren't enough scoundrels in your life. (He comes in close for a kiss)
Princess: I happen to like nice men.
Han: I'm a nice man.
Princess: No, you're not. You're --- (They kiss)

They are interrupted by C-3PO's cheerful, inopportune joy about repairing the ship and isolating the reverse power flux coupling.

Vader is summoned to alone speak to the commanding ruler of the galaxy, the Emperor (Ian McDiarmid/voice of Clive Revill) himself - a giant hologram, although the Emperor's face is hidden in a dark, hooded robe. The Emperor's voice is fearsome as he warns:

Emperor: There is a great disturbance in the Force.
Vader: I have felt it.
Emperor: We have a new enemy, the young rebel who destroyed the Death Star. I have no doubt this boy is the offspring of Anakin Skywalker.
Vader: How is that possible?
Emperor: Search your feelings, Lord Vader. You will know it to be true. He could destroy us.
Vader: He's just a boy. Obi-Wan can no longer help him.
Emperor: The Force is strong with him. The son of Skywalker must not become a Jedi.
Vader: If he could be turned, he would become a powerful ally.
Emperor: Yes. He would be a great asset. Can it be done?
Vader (promising with a stern oath as he bows and kneels): He will join us or die, master.

The wizened imp leads Luke to his peculiar little clay hovel during a downpour, where the small friendly creature serves a strange meal, but Luke is impatient to see Yoda and thinks he was wasting his time. The creature asks: "Why wish you become Jedi?" and Luke answers: "Mostly because of my father, I guess." The creature wearily mutters to himself as he turns away and speaks to Ben:

Yoda: I cannot teach him. The boy has no patience.
Ben's voice: He will learn patience.
Yoda: Hmm. Much anger in him, like his father.
Ben's voice: Was I any different when you taught me?
Yoda: No. He is not ready.
Luke: Yoda! I am ready. Ben - I can be a Jedi - Ben, tell him I'm -

Luke then realizes the creature is indeed Yoda, and is eagerly ready to be trained as a Jedi, but Yoda is contemptuous and accuses Luke of being only a dreamer of adventure, and reckless:

Yoda: Ready, are you? What know you ready? For 800 years have I trained Jedi. My own counsel will I keep on who is to be trained. A Jedi must have the deepest commitment, hmm? The most serious mind. (To Ben) This one a long time have I watched. All his life has he looked away to the future, to the horizon. Never his mind on where he was, hmm? What he was doing. Hmph! Adventure. Ha! Excitement. Ha! A Jedi craves not these things. You are reckless!
Ben's voice: So was I, if you remember.
Yoda: He is too old. Yes, too old to begin the training.
Luke: But I've learned so much.
Yoda: Ahh. (To Ben) Will he finish what he begins?
Luke: I won't fail you. I'm not afraid.
Yoda (ominously): Oh, You will be. You will be.