On one of her missions, the leader of the Latonans, called Marul, had denied the team's request to see the Sentinel, a powerful device capable of sending away any Goa'uld threat. Colonel Sean Grieves and Kershaw went behind the locals' backs and worked under the cover of darkness, dismantling the device, studying it and returning it exactly the way they found it, except they killed the Caretaker in the process. (SG1: "The Sentinel")