Lt. Col. Vincent Ruwet

Ruwet is Frank Olson's supervisor at Camp Detrick, a company man moving through the reenacted scenes of Errol Morris's docudrama with careful, official courtesy. He is there for the retreat where something goes wrong, present at the edges of decisions he did not make but must live inside of, watching more than speaking.

Shepherd plays him with the guarded blankness of institutional loyalty, a man whose face gives away only what he decides it should. Wormwood uses that stillness against him: every clipped answer and averted glance becomes evidence in a mystery the show refuses to resolve neatly, and Ruwet's composure is the mystery's most unsettling texture.