"Athena Sword is the first expansion for the PC version of Raven Shield. Athena Sword expands on the original by adding eight new missions, five new multiplayer missions, three new multiplayer gamemodes, and seven new weapons. Athena Sword was developed by Ubisoft-Milan and released on March 9, 2004. A Mac port was released on November 23, 2004. Athena Sword was packaged with the original game as Tom Clancy's Rainbow Six 3 Gold Edition in 2004.
The story begins in 2007. Team Rainbow neutralized the terrorist threat but Gutierrez, although in prison, still commands one of the terrorist cells. The terrorist cell strikes in Milan, Italy and team Rainbow is immediately called in to deal with this threat. The last terrorist action is to be set in Athens, Greece. Team Rainbow launches the operation Athena Sword and manages to prevent the attack. The final cut scene shows the prison guard who brings a newspaper to Gutierrez where he reads the news about prevented terrorist attack in Greece. On the last page he finds a small piece of paper with a message "It's over" and with Clark's signature. Two days later he is found hanged in his cell."
Source: Wikipedia, "Tom_Clancy's_Rainbow_Six_3:_Raven_Shield," available under the CC-BY-SA License.