Walter Donovan was a world-renowned collector of antiquities, and a colleague of Henry Jones, Sr.. Donovan donated heavily to the museum where Jones' son Indiana and Marcus Brody worked. He was revealed as a Nazi sympathizer who was ostensibly helping the Germans find the Holy Grail, but Donovan really wanted the Grail all to himself, planning to betray the Nazis after finally getting his hands on it. He used Indiana's skills to get past the many booby traps surrounding the Grail's hiding place, and upon getting in, sought to drink from the Grail and obtain eternal life.
Unfortunately for Donovan, he did not choose wisely. At the suggestion of the equally treacherous Dr. Elsa Schneider, he chose the most ornate drinking cup from among the vast selection, but it turned out to be the wrong one and, instead of being rewarded with eternal life, Donovan was punished with death. He underwent a rapid aging process, turning into a skeleton and then into dust.