The Circle

The Circle is a part of the Brotherhood of Steel.

Background
After the Brotherhood was defeated at HELIOS One, Christine Royce was sent after Elijah, the rogue elder. She carried a silenced sniper rifle and recon armor.

Appearances
The Circle is mentioned in the Fallout: New Vegas add-on Dead Money and Old World Blues.

Behind the scenes
According to Chris Avellone, the group was formed by hardliners in the Brotherhood of Steel, who believed the rest of the organization has drifted from the original principles of preserving tech.