Samantha Ruland's Murder was one of the story lines in Season Six of Scandal.
About
Samantha Ruland was killed by Rowan when he "rescued" her from The White House. When Rowan rescued her, he told both Ruland and Peus that he earned his freedom, he wanted a brand new password and to never be contacted by them ever again; Peus agreed and told Ruland to organise everything.
Murder
After Ruland gave Rowan his new passport and told him that he was free to go. Rowan pretended to show her the Dinosaur tooth in a box that had been delivered to his office. As Ruland turned around to talk to Rowan, he stabbed her with the Dinosaur tooth in the stomach. Shortly after killed Samantha, Rowan cut her head off and put it in a box, he then gave the head and the box to David Rosen so he could find out who hired her.