Female Wraith, responsible for keeping guard over the hibernating Wraith on their hive ship during the race's centuries-long slumber. The Keeper was defended by a small battalion of male foot soldiers, and was herself a deadman switch: When she was killed by Major John Sheppard, the entire Wraith population awakened.
The Keeper, like the others of her kind, possessed incredible rejuvenating abilities and psionic powers. After devouring the life-force of an Athosian whom they had captured, the Keeper interrogated Colonel Marshall Sumner and learned of the existence of Earth and its large population. Though the distant world presents a rich new feeding ground for the Wraith, she was not able to learn its location before Sumner's death. Before she could neutralize his life energy herself, Sumner was killed by Sheppard -- toward whom she then turned her fury.
Before the Keeper could do the same to him, however, Lieutenant Aiden Ford came to his rescue. Sheppard then impaled her through the chest with a Wraith rifle, killing her ... and ominously reawakening the rest of the species long before they normally would have finished their sleep cycle. The Wraith have again been set loose on the Pegasus Galaxy.
Rising, Part 2 - The Keeper begins interrogating the latest culled herd of humans, but is killed by Major Sheppard -- causing the entire population to awaken.