The Empress of the Racnoss is antagonist in Doctor Who, appearing in the episode "The Runaway Bride". She is the ruler of the Racnoss Empire.
She is a armoured red-skinned semi-humanoid life form with the lower body of a spider. She had a red crown-shaped head with four black eyes, a ventral spinneret for producing webbing, razor sharp spider-like limbs and a mouth with sharp fangs.
When the Racnoss Empire was destroyed by the Time Lords due to the arachnids' appetite resulting in the destruction of whole words, the last known remaining Racnoss, the children of the Empress, hid themselves by forming the core of what would become the planet Earth. The Empress was the only Racnoss to survive and not hibernate in the Earth's core. Instead, she orbited the Earth for billions of years in her Webstar ship, until her children called awakened and called out to her. The Empress then had the Torchwood Institute develop dangerous Huon particles, with which she could use to reawaken them. The ship then sent a signal to her Webstar which drew her to Earth.
The Empress met the Tenth Doctor on Christmas Day 2007, in a secret location under the Thames Flood Barrier. She was trying to awaken her race, whom she called her children, with the Huon energy implanted into the body of Donna Noble by her fiancé, Lance Bennett. Lance was originally affiliated with the Empress; however, when Donna escaped with the Doctor in the TARDIS, the Empress decided to use him instead. She force-fed him Huon particles and dropped him into the core of the Earth. There, the Huon particles awoke the Racnoss, who feasted on Lance.
Her plans to revive the Racnoss were foiled by the Doctor, who infiltrated the lair disguised as a Roboform. When she ordered her Roboforms to kill him, he used stolen controls to order them to "relax". He then offered to take the Racnoss species to a new planet, to coexist with all other life, but the Empress refused. Revealing his Time Lord origins and antagonising the Empress further, the Doctor sent bombs, disguised as baubles from a robotic Christmas tree, flying around the secret room. The bombs detonated, crashing into pipes, letting the River Thames flood into the room. The Empress was surrounded with fire, and the awakening Racnoss were drowned with the Thames water.
The Empress fled to her Webstar and vowed revenge on the Doctor and all of planet Earth by scorching it. However, the lack of Huon energy left the Webstar defenseless (thanks to her earlier attack on London), and the British Army destroyed it along with the Empress, presumably rendering the Racnoss extinct. The order to destroy the Webstar came from Harold Saxon himself, then Defence Minister.