Elsa (Alison Doody) is a bright, young historian from the country of Austria. She first meets Indiana Jones when he arrives in Venice to look for the Knight's Tomb. They work together to find it by navigating the catacombs underneath an old library in the city.
After finding the tomb, they are attacked by the Brothers of the Cruciform Sword. Elsa uses her ability to drive a speedboat in order to avoid the assault by the mysterious men. Eventually, Indiana captures their leader and he reveals the location of Indiana's kidnapped father.
Elsa's room is then ransacked, sparking an argument between her and Indiana. The argument soon leads to a passionate moment, filled with lust. Elsa goes with Indiana to Brunwald Castle in search of Henry Jones Sr. He leaves her behind in one of the rooms to swing into a locked room he suspects his father is being held captive in.
However, when Indiana and his father go to rendezvous with Elsa, they find her held at gunpoint by the Nazi Colonel Vogel. Despite his father's claim that Elsa, herself, is a Nazi, Indiana turns in his weapon to save her. But her true allegiance is indeed revealed to be with the Nazis when she slips her hand into Indiana's pocket to take the grail diary from him. With the betrayal complete and the recovery mission gaining significant progress, Elsa departs for a Nazi rally in Berlin, but before leaving, she gives Indiana a long, luscious kiss, telling him, "that's how Austrians say goodbye."
Elsa and Indiana do not meet again until the night of the rally. He confronts her to take the diary back. They argue about their ideologies, with Elsa claiming that she has no sympathy for the Nazi cause and instead believes in the grail. Indiana believes it does not matter what she thinks since she is on the side of evil. He threatens to squeeze her throat, and she retorts by saying all she would have to do is scream and the Nazis would be alerted to his presence. With that Indiana leaves her behind at the rally.
Elsa rejoins the expedition team with Donovan and heads to the Grail Temple while Indiana does battle with Vogel. Indiana and his party arrive at the Temple shortly after the Nazis. Donovan uses this to his advantage by shooting Henry Sr., forcing Indiana to get the grail for him. Elsa is visibly horrified by Donovan's actions, but is unable to do anything about the situation except watch Indiana deal with the three trials. Indiana does succeed in reaching the grail chamber where he meets an old knight. Elsa and Donovan enter the chamber moments later, with Donovan unsure which grail among the many is the true one.
Elsa once again shifts her allegiance by deliberately giving Donovan one of the false grails. He drinks from it and rapidly ages to his death, while trying to strangle Elsa with his deteriorating hands. Indiana rushes in to separate them and Donovan is reduced to dust. Elsa is able to calm down and collect herself to help Indiana choose the correct grail. He chooses a small, wooden cup and Elsa gives his a concerned look as he extracts the holy water to drink. However, she is relieved to see Indiana chose the correct grail, and she follows him back to Henry Sr. Before they go out from the chamber, the old knight warns them not to leave the temple with the grail. Indiana uses the holy water to heal his father's wounds and save him.
Elsa sees the grail resting on the temple floor and her eyes widen. She bends over and picks it up off the ground. She heads toward the exit, walking backwards closer to the Great Seal in the center of the temple. Indiana tells her to stop, but Elsa excitedly shakes the grail, insisting it is all theirs to take. Before his message can get across, her bootheel steps over the seal, and the temple starts collapsing.
Elsa loses her balance and falls on the ground. The grail rolls away from her grasp and she dives after it. In doing so, she knocks it into a large crack in the temple floor. She almost falls in herself, but Indiana lunges to grab her hands at the last moment. Elsa hangs on to Indiana, and looks below to see that the grail is lying on a small platform on the cliff wall. She immediately pulls a hand free to reach for it. Her hand hovers a few inches away from grasping the chalice, and as she reaches, the leather glove on her other hand begins slipping off. Indiana pleads with Elsa to give him her free hand, but she refuses to listen him, repeatedly whispering, "I can reach it..." Elsa continues to obsessively reach, ignoring Indiana. Her gloved fingertips almost touch the cup, and, just as she is about to grasp the grail, the glove on her other hand slips off. Elsa falls to her death, screaming.