Dr. Indiana Jones, a professor of archaeology at a small New England college, is better known to Army Intelligence as a cunning and steel-nerved adventurer. Indy Jones is the only man with the ability—and recklessness —to undertake the task demanded by his country on the eve of World War II. Jones has just returned from a recent expedition in the dense jungles of South America, which ended with the unwelcome intrusion of Rene Belloq, a ruthless French treasurehunter.

Indy leaves for Patan, Nepal to find one of his old professors who has information vital to his search. He finds the professor's beautiful and bold daughter Marion instead. Marion's father has died, leaving her to survive alone and penniless in the unfriendly foreign city, and making her the only one who can give Indy the help he needs. Reluctantly, she agrees to cooperate with the persuasive charmer, putting aside bitter memories of their past love affair for the right price (which is a chance to start a new life).

However, their reunion is cut short only days later in a crowded bazaar in Cairo, when Marion becomes the innocent victim of an attempt by German agents to dispose of Jones. Relentlessly pursued by Nazi henchmen, Indy soon learns that his old rival, Belloq, has been hired by the German archaeological team.

Indy's only chance now of keeping the object out of Nazi hands is to infiltrate their operation deep in the vast Egyptian desert before the Frenchman leads them to the site of the buried relic. The ancient ruins are teeming with life as Arabs work feverishly in the brutal sun, under the impatient supervision of Nazi officers. Once inside the encampment, Indy makes a more amazing discovery—Marion is still alive and being held prisoner. Time is quickly running out as the Nazis press forward at a frantic pace, growing ever closer to their final goal. Indy must risk going into the excavated ruins himself, aided by a small band of loyal Arabs and protected only by the darkness of the desert night. Finally, just as day begins to dawn, they find the awe-inspiring relic. But even Indiana Jones, a man of few fears, is not prepared for the terror that accompanies his brief triumph.

Seizing the treasure for their Fuehrer in Berlin, the Nazis leave the foolhardy American and his girlfriend to face a torturous death, while they hastily abandon the desecrated ruins. The defeated pair manage a harrowing escape in time for Indy to pursue the retreated convoy along a treacherous and winding road to Cairo and, in a heroically daring ambush, rescue the cargo from the enraged Germans.

Attempting to get the relic safely out of Cairo on a tramp steamer, Indy and Marion again find themselves trapped when their vessel reaches open sea. Triumphantly, the menacing Germans remove the relic to an awaiting submarine and, at Belloq's sinister prompting, abduct Marion as well.

Challenging his ingenuity and endurance to the limit, Indy follows them to their secret supply base, hidden deep within a remote tropical island. Here, in a tense climax, Indy confronts Belloq and the Nazis to a lightening-paced dramatic conclusion.