Atkins (The Day of the Doctor)
From Tardis Wiki, the free Doctor Who reference
Atkins was a guard at the Black Archive. By 2013, he had been working there for ten years, but believed it to be his first day due to the staff having their memories wiped at the end of every shift.
He granted a Zygon copy of Kate Stewart and Clara Oswald access when they visited the Archive. (TV: The Day of the Doctor) He was later killed by the Zygon. (PROSE: The Day of the Doctor)