Blake (The Christmas Invasion)

Major Blake — whose first name was either Richard (PROSE: Guinevere One) or Thomas (PROSE: The Christmas Invasion) — was the UNIT officer in charge of the Tower Ops branch of UNIT.

Biography
On 24 December 2006, Sgt Catherine Petts alerted other UNIT officers on a secure operations board on the UNIT website that the Guinevere One had gone missing. Major Richard Blake responded that he'd inform the PM, (PROSE: Guinevere One) Harriet Jones, (TV: The Christmas Invasion, et al.) betting that she'd use it as an excuse to visit the Tower Ops. (PROSE: Guinevere One) He escorted David Llewellyn to the Tower, and when Harriet Jones arrived, (TV: The Christmas Invasion) he told the UNIT officers on the operations board to be respectful and supportive, but not to let her think that she owned the place. (PROSE: Guinevere One)

In the Tower of London, Blake briefed Harriet Jones and Daniel Llewellyn on the protocols of dealing with extraterrestrial beings as the Sycorax invaded Earth. He was with them when all three were teleported aboard the Sycorax ship. After the death of Llewellyn, Blake tried to protect Harriet Jones and Alex by protesting Llewellyn's cold blooded death, but died when the Sycorax leader struck him with his death whip. (TV: The Christmas Invasion) A Sycorax scribe recorded the events of the invasion, including Blake's death, but was killed along with the other Sycorax. (PROSE: The Final Darkness)

After Major Blake's death, Sgt Catherine Petts was the one to announce it on a secure operations board to other UNIT officers. Soon thereafter, Major Jenny Maguire told them that Blake's family had been contacted, and that a memorial service was being arranged, at which the PM wished to speak at. (PROSE: Project Rooftop)

Personality
Outwardly, Blake was calm and respectful to the PM, (TV: The Christmas Invasion) but that seemed to be a façade, as he displayed a more irreverent tone behind her back, telling other UNIT officers that she'd probably use an excuse to enter the Tower Ops, and to not let her think that she owned the place. (PROSE: Guinevere One)

Behind the scenes

 * Major Blake is only addressed as "Major" in dialogue and the credits for The Christmas Invasion simply call him "Major Blake". In the short story Guinevere One, part of the Operations Board mini-series of narrative operations boards behind the secure login of the U.N.I.T. tie-in website, Blake's first name given as "Richard", whereas the novelisation gives him the name Thomas.
 * DWMSE 14 mentions that the UNIT website gave Richard as the forename.