Caleera

Caleera, also known as the Sonomancer, was a renegade Time Lord and a powerful psychic who was splintered across all of time, becoming the Red Lady.

Life on Gallifrey
Caleera studied at the Time Lord Academy and was a talented student who was prone to daydreaming. In one class, her Educator admonished her for this, leading to the discovery of Caleera's incredible psychic powers. Although she was greatly pleased to be special and wanted to hone her powers, she was given suppressants and surgery by a psychosurgeon (AUDIO: Scenes From Her Life) on Padrac's orders. (AUDIO: Stop the Clock)

She graduated with exceptional marks and was greatly upset when she was assigned to work as an assistant to a junior archivist for "a regeneration or two". (AUDIO: Scenes From Her Life) One day, she was summoned to Padrac's office and was charmed by him due to the low self-worth he had ensured she had. (AUDIO: Stop the Clock) She visited the Eleven in the Capitol prison facility and, on the day that he escaped, stole an antique TARDIS and kidnapped her Educator, the Chief Archivist and her psychosurgeon. (AUDIO: Scenes From Her Life)

As the Sonomancer
Anchoring the TARDIS in the Time Vortex, Caleera sealed herself in a neural amplifier and tested her powers on various prisoners, using the three Time Lords she kidnapped - now insane and calling themselves Lord Stormblood, Lady Sepulchra and Swordfish - as servants. She used her powers to destroy the homeworld of the Voord, attracting the Eighth Doctor's attention. When he, Liv Chenka and Helen Sinclair arrived in the TARDIS, she exploited Helen's empathy to get the Doctor to help her, after which she destroyed the TARDIS and left with her powers strengthened. (AUDIO: Scenes From Her Life)

Caleera went to the High Sierra in 1905 and gave her Gift to Sam Sonora, experimenting with her powers by having them amplify the 1906 San Francisco earthquake and destroy Earth. She later transferred the Gift to the Doctor, who thwarted her by using it to power his TARDIS instead. (AUDIO: The Gift)

Now calling herself the Sonomancer, she planned to destroy Syra and encountered the Doctor once again, offering him the chance to join the Doom Coalition. He escaped her using the remainder of the Gift in his mind, after which she destroyed the planet and rescued the Eleven by teleporting him into his TARDIS. (AUDIO: The Sonomancer)

The Sonomancer took up residence within the Matrix and searched for the plans for the Resonance Engine, as well as distorting information to mislead the High Council. She discovered that the Doctor, Liv and Helen were still alive and informed Padrac that Chancellor Jerasta made contact with the President, after which he ordered her to destroy the Presidential TARDIS. She also wiped out the councillors who opposed Padrac's plans and tortured River Song in the Matrix.

At the Eleven's request, the Sonomancer traced the Doctor so that he could follow and kill him. (AUDIO: Songs of Love) She assisted him by negotiating with the Weeping Angels and causing a power cut in New York City. (AUDIO: The Side of the Angels)

The Sonomancer located the plans for the Resonance Engine, which Padrac then built and sealed her inside with Ladonne's help. However, she learnt of how Padrac had manipulated her life and how he did not love her after the Doctor convinced her to look into the Matrix, leading her to send a message to Liv to lower the Capitol shields and to transfer her powers to Helen, having her pilot a Battle TARDIS into the machine. Whilst the TARDIS was thrown into the Vortex, the Sonomancer was scattered across time. (AUDIO: Stop the Clock)

As the Red Lady
Fractured across time and searching for Padrac, the Sonomancer became known as the Red Lady, inhabiting artwork and killing the first to look upon her unless they created more art. (AUDIO: The Red Lady, Stop the Clock) Dr Francis McCallum assembled a collection of all such art after the Red Lady killed his mother and and father which Albert Kennedy donated to the National Gallery after his death.

The Red Lady killed Kennedy and Professor Walter Pritchett before coming for the Doctor and Liv. The two were able to trap her by drawing a stick figure and writing a poem respectively, after which the Doctor removed the collection. (AUDIO: The Red Lady) Some remained, with a sealed vault in the Relic Room containing one of the last to survive. (AUDIO: The Web of Time)

Eventually, the Red Lady found Padrac in the Capitol as a discolouration on his cell wall which grew. She spoke to him before he was frozen, telling him that they would be together forever. (AUDIO: Stop the Clock)

Personality
To be added.

Appearance
Caleera was beautiful and had red hair. (AUDIO: The Red Lady, Stop the Clock) She wore green, which River Song thought looked good with her hair colour. (AUDIO: Songs of Love)