Indiana Jones and the Last Crusade: The Graphic Adventure was released in 1989 at the same time as the film. It was developed and published by Lucasfilm games (now LucasArts). It's a point and click adventure game designed by Ron Gilbert, Noah Falstein, and David Fox. It was released on Amiga, Atari ST, DOS, Macintosh and FM Towns.
Last Crusade is the 3rd game to run on the SCUMM engine. The gameplay is point and click adventure, that included a point system called IQ or “Indy Quotient”. To reach the maximum of 800 IQ, the player would have to find alternate solutions to puzzles. This gave the game additional replay value.
It's a beautiful looking game. Attention was clearly paid to the animation. Unlike Indiana Jones And The Fate Of Atlantis, The Last Crusade is a wonderful companion to the film and expands on some of the info from it. Many scenes of the game have been conceived personally by George Lucas and Steven Spielberg during the creation of the film. If you're looking for a good movie tie-in, this is the one.