With his companions, he explores time and space, faces a variety of foes and saves civilizations, helping people and righting wrongs.

He also travels briefly with unruly boy-genius Adam Mitchell, played by Bruno Langley, and with 51st-century con man and former "Time Agent" Captain Jack Harkness, portrayed by John Barrowman.

[9] After the announcement that the show would be returning, Davies revealed that the new companion would "probably" be called Rose Tyler in an edition of Doctor Who Magazine published in November 2003.

[11] Piper was announced as portraying Rose Tyler on 24 May,[12][13] a character which fulfilled the role of permanent companion during the series, and was welcomed by fans of the show.

Paul Abbott was scheduled to write an episode for the series which would have revealed that Rose's entire life had been manipulated by the Doctor in order to mould her into an ideal companion.

[18] In a 2010 interview, Eccleston revealed that he left the show because he "didn't enjoy the environment and the culture that [they], the cast and crew, had to work in", but that he was proud of having played the role.

[19][20] The character of Adam Mitchell was first conceived, along with Henry van Statten, during Davies' pitch to the BBC, in a story heavily based on Robert Shearman's audio play Jubilee called "Return of the Daleks".

[21] John Barrowman appears as Captain Jack Harkness, a character introduced in "The Empty Child", where he joined the TARDIS crew for the final five episodes of the series.

[24] Following on that arc, the character's debut episode would leave his morality as ambiguous, publicity materials asking, "is he a force for good or ill?

Barrowman says that at the time of his initial casting, Davies and co-executive producer, Julie Gardner had explained to him that they "basically wrote the character around [John]".

Tennant initially believed the offer was a joke, but after he realised they were serious, he accepted the role and first appeared in the series finale "The Parting of the Ways".

[30] Other actors and television presenters who appeared in the series included Mark Benton,[30] Zoë Wanamaker,[31] Simon Callow,[32] Eve Myles,[32] Penelope Wilton,[33] Annette Badland,[33] David Verrey,[33] Matt Baker,[33] Andrew Marr,[33] Corey Johnson,[34] Simon Pegg,[35] Anna Maxwell-Martin,[35] Tamsin Greig,[35] Shaun Dingwall,[36] Florence Hoath,[37] Richard Wilson,[37] Jo Joyner,[38] Davina McCall,[38] Paterson Joseph,[38] Anne Robinson,[38] Trinny Woodall,[38] and Susannah Constantine.

[38] During the late-90s, Davies, a lifelong Doctor Who fan, lobbied the BBC to revive the show from its hiatus and reached the discussion stages in late 1998 and early 2002.

[44] His pitch was submitted for the first production meeting in December 2003, with a series of thirteen episodes obtained by pressure from BBC Worldwide and a workable budget from Julie Gardner.

[45] During early production the word "Torchwood", an anagram of "Doctor Who", was used as a title ruse for the series while filming its first few episodes and on the daily rushes to ensure they were not intercepted.

[48] Davies also approached his friend Paul Abbott and Harry Potter author J. K. Rowling to write for the series, but both declined due to existing commitments.

[57] The start of filming created stress among the production team because of unseen circumstances: several scenes from the first block had to be re-shot because the original footage was unusable; the Slitheen prosthetics for "Aliens of London", "World War Three", and "Boom Town" were noticeably different from their computer-generated counterparts; and, most notably, the BBC came to a gridlock with the Terry Nation estate to secure the Daleks for the sixth episode of the series, to be written by Rob Shearman.

[66] The BBC released a statement that the source of the leak appeared to be connected to the Canadian Broadcasting Corporation, which responded by stating that they "are looking into it.

[68] In some regions, the first few minutes of the original BBC broadcast of "Rose" on 26 March were marred by the accidental mixing of a few seconds of sound from Graham Norton hosting Strictly Dance Fever.

[69] In the United States, the Sci Fi Channel originally passed on the new series as it found it lacking and believed it did not fit in its schedule,[64] but the network later changed its mind.

After it was announced that the first series would start in March 2006, Sci Fi Channel executive vice president Thomas Vitale called Doctor Who "a true sci-fi classic", with creative storytelling and colorful history, and was excited to add it to its line up.

[70] Doctor Who finally debuted in the U.S. on the Sci Fi Channel on 17 March 2006 with the first two episodes airing back-to-back, one year after the Canadian and UK showings.

[111] The initial Sci Fi Channel broadcasts of the series attained an average Nielsen Rating of 1.3, representing 1.5 million viewers in total.

[115] In April 2004, Michael Grade returned to the BBC, this time as the Chairman of the Board of Governors, although this position does not involve any commissioning or editorial responsibilities.

[116] Although he had previously disliked the show and imposed an eighteen-month hiatus on it during the Sixth Doctor era, he eventually wrote an e-mail to the Director-General of the BBC Mark Thompson in June 2005, after the successful new first series, voicing approval for its popularity.

His only criticism was about the new TARDIS interior, though he did comment that he was "also a bit dismayed that more wasn't made of the show's incidental music, which seemed fairly anonymous in the background".

[118] Robin Oliver of The Sydney Morning Herald praised Davies for taking "an adult approach to one of television's most famous characters" that children would appreciate, and that he reinvented it in a way that would be "competitive in a high-tech market".

[119] Reviewing the first episode, The Stage's Harry Venning hailed it as a "fabulous, imaginative, funny and sometimes frightening reinvention" and particularly praised Rose for being an improvement upon previous female companions who were "fit only to scream or be captured".

[120] Digital Spy's Dek Hogan found the final episode anticlimactic, but overall said that the series was "excellent Saturday night telly of the kind that many of us thought the BBC had forgotten how to make".

However, he was critical of Davies' "annoying tendency to play to the lowest common denominator with toilet humor", but felt that from "Dalek" on the series was more dramatic and sophisticated.