Gideon Vandaleur

Gideon Vandaleur was an envoy of the Silence. Six months after his death, the Teselecta had assumed his form while investigating the Silence. The Doctor visited the Teselecta, posing as Vandaleur, and asked him for information about the Silence, specifically their weakest link. The Teselecta then told him that it was Gantok. (DW: The Wedding of River Song)