Diana Burnwood is Agent 47's controller at the International Contract Agency -- the ICA or "the Agency". Diana briefs number 47 on assignments, oversees his progress and serves as a guide. For the majority of the Hitman series, 47 and Diana never meet face to face, with the assassin only recognizing her by voice. They eventually meet during the conclusion of Contracts, and during Blood Money. Preceding the events in Blood Money, it is implied Diana is promoted to a higher position within the Agency.
Diana Burnwood is voiced by Vivienne McKee.
In the fifth game of the Hitman series, Hitman Absolution, the character of Diana Burnwood is voiced by Marsha Thomason. But since the new Glacier 2 game engine uses motion capture in many of it's scenes, Marsha Thomason have not only been giving voice to Diana Burnwood, she has also been playing her in her in the motion capture studio, Giant Studios, where some scenes have been shot.
All this plus more information was given through the interview " Hitman: Absolution - Marsha Thomason Interview", which was launched on youtube on February 20th 2012.
Facts about Diana Burnwood prior to Hitman: Absolution
In 1990 Diana was launch into the ICA controller/handler programme, after being in the ICAs eye of attention for a couple of years. Over the next few years Diana excels in the programme and the ICA quickly discovers her talent.
Her "first" appearance was in the first Hitman installment Hitman: Codename 47, where she for the first time had her own assignment which was, at the time, the pretty unknown Agent 47. Early on she only communicated via text communication with Agent 47. The first time that both Agent 47 and the player hears her voice is when she tells Agent 47 to be careful before a mission starts.
The next time ,since Hitman: Codename 47, that you see or hear anything about Diana Burnwood is in the 2nd Hitman franchise Hitman: Contracts. In this instalment she is seen talking to Agent 47 in the beginning of the game, which makes her more interesting as a person due to the fact that she is getting closer to Mr. 47.