Restac

Restac was a Silurian, and also a Commander in the Silurian military.

Biography
Her twin sister Alaya kidnapped people from Earth's surface and locked them up, presumably for experimentation. This could be seen as some form of payback for the Humans drilling down (unknowingly) into their underground city. Restac was wholly adamant on provoking a war, so that she could reclaim the Earth from the Human Race. Angered when ordered by Malokeh (who was also a Commander in the military, but preferred his laboratory) and Eldane (the leader of the Silurians) to put down her weapon after threatening to execute the Doctor, Amy Pond and Nasreen Chaudhry, she went on a revenge-driven rampage. Restac then went on to threaten the humans and even went as far as killing Malokeh. She was angered to discover that Ambrose Northover had murdered her sister, Alaya, she then went on to drive the humans out, but Eldane released a deadly gas, forcing Restac's warriors to retreat back to their hibernation chambers. Restac refused to leave, and was poisoned by the gas. With her dying breath, she fired a shot at the Doctor, but Rory Williams intervened, and took the blow. (DW: Cold Blood)

Behind the scenes
The events of DW: The Big Bang has led to speculation as to whether certain events depicted prior to the story, including Restac's shooting of Rory, ever happened.