Martha Jones:

Martha joined the Doctor during the episode "Smith and Jones", the first episode of series 3. She left at the end of the series and the intention was that she would appear in other series' and in Torchwood and the Sarah Jane Adventures. But due to Freema Agyaman's schedule, she appeared only one further series of Doctor Who and in three episodes of Torchwood, series 2.

Martha was a medical student in a London hostpital, which was picked up and relocated on the moon by the Judoon. The Doctor had arrived at the hospital shortly before the event, ostensibly as a patient. Intrigued by him, Martha joined the Doctor in saving the hospital and saved his life by giving him her last breath. Afterwards, to thnk her, the Doctor took her on an adventure (the episode "The Shakespeare Code") but she joined him up as his companion. Martha, being an adventurous young woman, was attracted to the Doctor. But he was still grieving the loss of Rose and was oblivious to Martha's interest. Although he gave her a key to the Tardis. During "Human Nature"?"The Family of Blood" affair, Martha kept the secret of the Doctor's identity alive while working as a maid in a boy's boarding school during the Edwardian era. She had to watch while he, beliving himself to be human, fell in love with the school matron.

Martha's time in the Tardis ended with the cataclysmic last three episodes, when the Master finalised his plans to take over the Earth. She spent a year, travelling around the world alone. Her work enabled the Doctor to overcome the Master and reverse time, so that the terrible year of slavery and despair the world endured never happened. Martha's family were traumatised by their part in the events and so she decided to leave the Doctor and support them. She also realised that the Doctor was never going to fall in love with her.

Martha went on to receive her medical degree and she become a medical officer in UNIT. She was temporarily drafted to Torchwood Cardiff, who needed an expert on alien life. When the group's own doctor, Owen Harper was killed, she became Torchwood's medical officer, until Owen was declared fit to return to active duty, following his resurrection. Martha, by then a much more confident and assertive person, summoned the Doctor to return to Earth and help UNIT fight the Sontaran invasion. Once again worked with the Doctor, and his new companion, Donna Noble. Promoted to work in a USA division of UNIT, she helped to create a teleportation system, based on the one used by the Sontarans. She joined the Doctor and other companions in overcoming the Daslks. At the end, she was seen in company with Captain Jack Harkness and Micky Smith, with the Captain trying to persuade her to rejoin Torchwood. Instead, she marries Mickey and they go off on their own adventures to fight aliens together.

Martha was an interesting person while she accompanied the Doctor. She never shirked from danger, proved herself to be loyal and trustworthy and was always ready for adventure. At the beginning, although she lived alone and was training to become a doctor, she struggled with trying to cope with a rather overbearing and over-protective mother, and siblings who relied heavily on her. Her year apart from everyone, and learning to survive in the hostile world made by the Master and the Toclofen, brought out her self reliance and her courage and determination. It is no wonder that after she left the Doctor, she found her feet as a UNIT officer and then with Torchwood. Perhaps she would have joined Captain Jack, but she married Mickey instead. He had also changed a great deal after his experiences with the Doctor and the alternative dimension when he joined the fight against the Cybermen. She coped very well with her unrequited feelings for the Doctor.

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