Dr.  Martha Jones is a fictional character who is played by Freema Agyeman in the television series Doctor Who and its spin-off series, Torchwood. She is a companion of the Tenth Doctor in Doctor Who, replacing Rose Tyler in the role of the main companion. She made her first appearance in Series 3's "Smith and Jones", broadcast in the UK on 31 March 2007.

Appearances

Television

Martha Jones is introduced in the 2007 series of Doctor Who, first appearing in the episode "Smith and Jones".  When the hospital she works at is moved to the Moon,  Martha helps save the day alongside an alien time traveller known only as the Doctor (David Tennant). To thank her for her help, the Doctor invites her to join him for one trip in his time machine the TARDIS, but he later accepts her as his full-time "companion", admitting that she was "never just a passenger", and he even gives her the key to the TARDIS. Nevertheless, she becomes frustrated because the Doctor does not realise her feelings for him, When the  Doctor falls in love(while believing himself to be a human) in the "Human Nature"/"The Family of Blood" two-parter, a pained Martha claims "You had to go and fall in love with a human... and it wasn't me". In the last episode of the series she spends a year travelling the world in a plan which saves the Doctor and reverses time, undoing the Master's actions.

The character reappears in the 2008 series of the Doctor Who spin-off Torchwood, which focuses on occasional Doctor Who companion Jack Harkness. She first appeared in the episode "Reset" as part of a three-episode story, 
Later in the Fourth Series of Doctor Who, Martha returns for a three-episode arc beginning with "The Sontaran Stratagem" and ending with "The Doctor's Daughter", Agyeman appears in the role again for the final two episodes of the series, "The Stolen Earth"/"Journey's End",where she has been promoted to a US division of UNIT.

Other Appearances
Aside from television appearances, the character of Martha also appears in Doctor Who novels and comic books, some of which it is unknown if they are canon or not.

In books, Martha appears in the "New Series Adventures" series of Doctor Who novels, published by BBC Books. The first book published was a "Quick Reads" novel, Made of Steel by Terrance Dicks (published before  her first television appearance), and the character subsequently appeared in all novels in the series, starting with Sting of the Zygons by Stephen Cole and most recently in The Many Hands by Dale Smith. Freema Aygeman appears as the character on the cover of every novel. In late 2008 The Story of Martha, a collection of stories focusing on Martha's adventures between "The Sound of Drums" and "Last of the Time Lords", will be published.

In comic strip apperences,Martha has appeared in the Doctor Who Magazine strips from #381 onwards and the Doctor Who Adventures comics from #28 onwards. The character also appears in the Battles in Time series of comic books periodically. In 2007, American comic book publisher IDW Publishing announced their plans to do a series of Tenth Doctor and Martha comics for a America. When asked about canonicity, IDW executive editor Chris Ryall dodged the issue by saying all the comics are "blessed" by Russell T Davies but it is up to the individual how canonical each story is.

Martha also appears in a Radio 4 Torchwood drama, "Lost Souls" which aired in Summer 2008.

References

Other websites
 Martha Jones on the BBC's Doctor Who website
 Martha Jones on FreemaAgyeman.com
 Martha Jones' Myspace page

Doctor Who characters

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