In the spring of 1936 an exploration party penetrates thick jungle on the South American continent.
Satipo: [picking up poison dart] The Hovitos are near. The poison is still fresh, three days. They're following us.
Barranca: If they knew we were here, they would've killed us already.
When the group's leader stops to examine map fragments, another of the group pulls a gun. The leader, hearing the click as the turncoat chambers a round, pulls out a bullwhip and disarms the man, sending him fleeing back through the jungle.
The man who expertly wields the bullwhip is Dr. Henry "Indiana" Jones, Jr. (Harrison Ford), an archaeologist with a reputation for heavy-handed field work that takes him around the globe in search of ancient treasures.
Indy and his remaining companion, Sapito (Alfred Molina), enter a dank and oppressively vast cave.
Indiana: This is it... This is where Forrestal cashed in.
Satipo: A friend of yours?
Indiana: A competitor... he was good. He was very good.
Inside the cave are several traps rigged by the ancient people who hid a small, valuable statue there -- and one of the traps is found to have snared Forrestal.
Jones finds the antechamber where the statue sits atop a pedestal and is protected by an elaborate system of traps.
Satipo: Let us hurry. There is nothing to fear here.
Indiana: That's what scares me.
Indy presses a floor stone with a branch that triggers a dart to shoot from the wall and hits the branch.
Indiana: Stay here.
Satipo: [shrugs] If you insist, se´┐Żor.
Jones avoids the booby-trapped stones and makes it to the idol. He very deftly replaces the idol with a bag of sand, judging the weight of the treasure by sight.
However, the weight is not precise, the pedestal sinks and the chamber begins to disintegrate. Jones runs, narrowly avoiding the darts. When he arrives at a bottomless pit he & Sapito had crossed earlier using Jones' bullwhip, Sapito crosses safely using the whip.
Indiana: Give me the whip.
Satipo: Throw me the idol. No time to argue! Throw me idol, I'll throw you the whip!
Indiana: [throws the idol] Give me the whip!
Satipo: Adi´┐Żs, se´┐Żor.
Sapito drops the whip and runs off. Jones manages to jump across and pull himself up and escape under the stone door that closes. He finds Sapito dead, killed by the same trap that killed Forrestal.
Indiana: Adios, Satipo...
Jones retrieves the idol and must once again flee while a large boulder rushes toward him.
Seemingly safe, Indy is cornered by the Hovitos, the local tribe, who are led by Dr. Rene Belloq (Paul Freeman), an arrogant French archaeologist who is a longtime rival and enemy of Indy's.
Belloq: Dr. Jones. Again we see there is nothing you can possess which I cannot take away.
Indiana: Too bad the Hovitos don't know you the way I do, Belloq.
Belloq: Yes, too bad. You could warn them... if only you spoke Hovitos!
Indy flees and is rescued by Jock (Fred Sorenson), flying a seaplane . . . . .
Indiana: There's a big snake in the plane, Jock!
Jock: Oh, that's just my pet snake Reggie.
Indiana: I hate snakes, Jock! I hate 'em!
Jock: Come on! Show a little backbone, will ya!
Back stateside, Indy teaches an archeology class and is still upset over the loss of the statue.
Indiana: [to students] This site also demonstrates one of the great dangers of archaeology; not to life and limb, although that does sometimes take place. I'm talking about folklore.
He explains to his friend Marcus Brody (Denholm Elliott), his guess is Belloq is taking the statue to Marrakesh. Indy has found pieces he feels will pay for a trip to Marrakesh to find Belloq. But Marcus dashes that hope by informing him that two Army Intelligence officers want to talk to him.
Major Eaton: Doctor Jones, we've heard a great deal about you.
Indiana: Have you?
Eaton: Professor of Archeology, expert on the occult, and how does one say it... obtainer of rare antiquities.
Indiana: That's one way of saying it. Why don't you sit down, you'll be more comfortable.
Colonel Musgrove: Yes, you're a man of many talents.
Eaton: Now, you studied under Professor Ravenwood at the University of Chicago.
Indiana: Yes, I did.
Eaton: You have no idea of his present whereabouts?
Indiana: Only rumors, really. Somewhere in Asia, I think. I haven't really spoken to him in ten years. We were friends once, but we had a bit of a falling out, I'm afraid.
Musgrove: Now, Doctor Jones, you must understand that this is all strictly confidential.
Indiana: I understand.
Musgrove: Yesterday afternoon, our European section intercepted a German communique that was sent from Cairo to Berlin.
Eaton: You see, for the last two years, the Nazis have had teams of archaeologists running around the world looking for all sorts of religious artifacts.
Hitler's a nut on the subject. He's crazy. He's obsessed with the occult. And right now, apparently, there is some kind of German archaeological dig going on in the desert outside Cairo.
Musgrove: Now, we got some information here, but we can't make anything out of it and maybe you can. "Tanis development proceeding. Acquire headpiece, Staff of Ra, Abner Ravenwood, US."
Indiana: The Nazis have discovered Tanis!
Eaton: Now just what does that mean to you... 'Tanis'?
Indiana: Tanis is one of the possible resting places of the Lost Ark.
Musgrove: The Lost Ark?
Indiana: Yeah, the Ark of the Covenant. The chest the Hebrews used to carry the Ten Commandments around in.
Eaton: Alright now, what do you mean the Ten Commandments, you're talking about THE Ten Commandments?
Indiana: Yes, the actual Ten Commandments. The original stone tablets that Moses brought down out of Mount Horeb and smashed, if you believe in that sort of thing. Didn't you guys ever go to Sunday School? Look, the Hebrews took the broken pieces and put them into the Ark. When they settled in Canaan, they put the Ark in a place called The Temple of Solomon . . .
Brody: In Jerusalem.
Indiana: . . . where it stayed for many years, until all of a sudden... whoosh, it was gone.
Indiana: Nobody knows where or when.
Brody: However, an Egyptian pharaoh...
Brody: ...yes, invaded the city of Jerusalem round about 980 B.C., and he may have taken the Ark back to the city of Tanis and hidden it in a secret chamber called The Well of Souls.
Eaton: [skeptically] Secret chamber?
Brody: However, about a year after the pharaoh, who had returned to Egypt, the city of Tanis was consumed by the desert in a sand storm which lasted a whole year. Wiped clean by the wrath of God.
Eaton: [turns slowly toward Musgrove] Uh... huh.
Musgrove: Obviously, we've come to the right men. Now you seem to know, uh, all about this Tanis, then.
Indiana: No, no, not really. Ravenwood is the real expert. Abner did the first serious work on Tanis. Collected some of its relics. It was his obsession, really. But he never found the city.
Eaton: Frankly, we're somewhat suspicious of Mr. Ravenwood, an American being mentioned so prominently in a secret Nazi cable.
Brody: Oh, rubbish. Ravenwood's no Nazi.
Musgrove: Well, what do the Nazis want him for then?
Indiana: Well, obviously, the Nazis are looking for the headpiece to Staff of Ra and they think Abner's got it.
Eaton: What exactly is a headpiece to the Staff of Ra?
Indiana: Well, the staff is just a stick. I don't know, about this big. Nobody really knows for sure how high. And it's...
Indy turns the blackboard to the blank side and starts sketching.
Indiana: it's, uh... it's capped with an elaborate headpiece in the shape of the sun with a crystal in the center. And what you did was, you take the staff to a special room in Tanis, a map room with a miniature of the city all laid out on the floor. And if you put the staff in a certain place at a certain time of day, the sun shone through here and made beam that came down on the floor here... and gave you the exact location of the Well of the Souls.
Musgrove: Where the Ark of the Covenant was kept, right?.
Indiana: That's exactly what the Nazis are looking for.
Eaton: Now what does this Ark look like?
Indiana: Uh... there's a picture of it right here.
Indy opens a book on the table.
Indiana: That's it.
They all look at an illustration of the Hebrews devastating their enemy with the Ark.
Eaton: Good God!
Brody: Yes, that's just what the Hebrews thought.
Musgrove: [pointing to a beam of light] Uh, now what's that supposed to be coming out of there?
Indiana: Lightning. Fire. Power of God or something.
Eaton: I'm beginning to understand Hitler's interest in this.
Brody: Oh, yes. The Bible speaks of the Ark leveling mountains and laying waste to entire regions. An army which carries the Ark before it... is invincible.
Later that evening, Brody arrives at Indy's home and informs him the Army officers will finance his trip. Indy figures his first lead is to find Marion Ravenwood (Karen Allen), daughter of Abner.
Brody: Marion's the least of your worries right now, believe me, Indy.
Indiana: What do you mean?
Brody: Well, I mean that for nearly three thousand years man has been searching for the lost ark. It's not something to be taken lightly. No one knows its secrets.
It's like nothing you've ever gone after before.
Indiana: [laughing] Oh, Marcus. What are you trying to do, scare me? You sound like my mother. We've known each other for a long time. I don't believe in magic, a lot of superstitious hocus pocus. I'm going after a find of incredible historical significance, you're talking about the boogie man. Besides, you know what a cautious fellow I am.
Indy throws his gun into his suitcase.
Indy flies to Nepal, followed by a Nazi agent, Toht (Ronald Lacey), to confront Marion.
Marion runs a restaurant and bar, and can outdrink anyone.
Indiana: Hello, Marion.
Marion: Indiana Jones. I always knew some day you'd come walking back through my door. I never doubted that. Something made it inevitable. So, what are you doing here in Nepal?
Indiana: I need one of the pieces your father collected.
Marion surprises him with a right cross to the jaw.
Marion: I've learned to hate you in the last ten years!
Indiana: I never meant to hurt you.
Marion: I was a child. I was in love. It was wrong and you knew it!
Indiana: You knew what you were doing.
Marion: Now I do. This is my place. Get out!
Indy explains he's looking for the headpiece and thinks Abner may have collected it. Marion informs him Abner is dead.
Indiana: I can only say I'm sorry so many times.
Marion: Well, say it again anyway!
Marion, still bitter over their breakup, nonetheless accepts when Indy offers her $3,000 and the promise of more when they return stateside. She is cryptic about the headpiece, and after Indy leaves she ponders it as she wears it around her neck.
Toht and several Sherpa heavies enter the bar . . .
Toht: Good evening, Fraulein.
Marion: The bar's closed.
Toht: [chortling] We uh . . .We are . . . not thirsty.
Marion: What do you want?
Toht: Ah, the same thing your friend Dr. Jones wanted. Surely he told you there would be other interested parties?
Marion: Must have slipped his mind.
Toht: The man is nefarious. I hope for your sake that he has not yet acquired it.
Marion: Why, are you willing to offer more?
Toht: Oh, almost certainly. Do you still have it?
Marion: [blows smoke in his face] No, but I know where it is.
Toht: Your fire is dying . . . here, why don't you tell me where the piece is right now?
Marion: Listen, Herr Mac, I don't know what kind of people you're used to dealing with, but nobody tells me what to do in my place.
Toht: Fr´┐Żulein Ravenwood, let me show you what I am used to . . .
They hold Marion hostage, with Toht ready to torture her with a hot poker, for the headpiece.
Marion: Wait, wait! I can be reasonable!
Toht: That time has passed.
Marion: You don't need that. I'll tell you everything!
Toht: Yes, I know you will.
Indy returns and a firefight erupts during which the fireplace logs are dislodged and the building begins burning down. Indiana is being strangled against the bar. He looks up at Marion . . . . .
Marion hands him the whiskey bottle and he smashes it over his assailant's head.
Toht: Shoot them. Shoot them both.
Toht finds the headpiece but when he grabs it he's badly burned -- leaving an image of one side of the headpiece branded on his hand. He escapes while Indy and Marion do likewise. Marion grabs the headpiece before running out of the burning bar.
Marion: Well, Jones, at least you haven't forgotten how to show a lady a good time.
Indiana: Boy, you're something!
Marion: Yeah? I'll tell you what. Until I get back my five thousand dollars, you're gonna get more than you bargained for. I'm your goddamn partner!