Resurrection is a modification for Fallout 2. It has a completely new story and takes place in New Mexico, sometime between the events of Fallout 1 and 2. It's as if there had been a third classic Fallout game.
Fallout 1.5: Resurrection patch version 1.5 EN installation file. The patch can be applied to Resurrection version 1.4
Fallout 1.5: Resurrection installation file. Version 1.5 EN
Fallout 1.5: Resurrection installation file. Version 1.4 EN