"The Operative: No One Lives Forever stars female protagonist and spy Cate Archer. The game is a mixture of a first-person shooter and a first-person sneaker: most (but not all) missions can be solved in multiple ways: using sneaking to avoid danger, using gadgets, or by going in with guns blazing.
The basic plot of the game is that a secret organization, UNITY, watches over world peace. Seven UNITY agents are murdered within a week, leaving UNITY with a critical manpower shortage. In response, Cate Archer (an ex-cat burglar) is given a role as field agent to try to discover the cause of the agent assassinations. All roads lead to a new terrorist organization named H.A.R.M., run by a colorful assortment of characters intent on destroying the free world.
Source: Wikipedia, "The_Operative:_No_One_Lives_Forever," available under the CC-BY-SA License.