Scott Kingsley was an agent of the CIA. He was ambushed on board a bullet train and killed by Gordei Volkov, a hitman working for the Covenant.
Season 3
Scott was seen on board a train sitting next to a young woman in the adjacent seat. A few moments later, sutied men with guns came into the train car and started killing everyone they came in contact with, aiming for Kingsley. Kingsley fought back, shooting at a few assailants while running through the train, discovering several bodies. Then the doors in front of him hissed open, revealing a Russian hitman and two of his thugs.
With nowhere else to run, Kingsley was trapped in the train car. The hitman shot Kingsley in the leg and kneeled over to him, demanding to tell him where a certain item of value was. Kingsley didn't say anything, so the hitman stabbed him in the chest. Kingsley eventually told him that it was in his shoe, but when the hitman's thugs went to check the device, it wasn't accurate. The hitman stabbed Kingsley again, this time fatally, and found a tiny chip in one of his pockets, the item he was searching for all along.