[2][3] The central plot of Miracle Day is that suddenly no one on Earth can die, which impels increasingly troublesome legislative changes around the world as the global population soars.

[10] On the same day on Earth, the concept of death is suddenly nullified when it is found that people who have suffered mortal wounds or fatal diseases are unable to die.

Torchwood recognizes that the Families manipulated events just prior to the first day of the miracle in Shanghai and Buenos Aires, two points on opposite sides of the globe.

Later, as the world deals with the concept of death again and Torchwood attends Esther's funeral, Rex is shot at by a Families mole in the CIA.

Early development rumours suggested that the fourth series would be a reboot of the show, and that it would air on Fox Network in the United States.

[citation needed] Gardner and Davies spent four weeks alongside their writing staff working through the complete story.

[17] The writing team chose to revise each episode before the first scene was shot; writer Jane Espenson felt this would give the series a much tighter feel and greater overall continuity.

[19] Other returning characters included Gwen's former police partner PC Andy (Tom Price), now a sergeant,[20] and her parents Geraint (William Thomas) and Mary Cooper (Sharon Morgan), who previously appeared in the 2008 Torchwood episode "Something Borrowed".

[21][22][23] Mekhi Phifer joined the show as Rex Matheson,[24] the CIA's "golden boy" operative, fast-tracked for career stardom.

[26] Arlene Tur was cast as surgeon Vera Juarez,[27] while Bill Pullman played Oswald Danes,[25] a dangerous convicted child sex offender and murderer who turns a prison release into celebrity status.

[28] Oswald faces lethal injection, but becomes swept up in the story's plot thread when he — like the rest of the world — simply does not die.

[29] Guest stars included Lena Kaur,[30] Dichen Lachman,[26] Wayne Knight, Ernie Hudson, C. Thomas Howell,[31] John de Lancie,[32] Nana Visitor and Dillon Casey.

[35] During the development phase, actor James Marsters expressed strong interest in returning as his Series 2 character Captain John Hart.

[54] Actors John Barrowman and Bill Pullman, alongside executive producer Julie Gardner, attended the 2011 MIPTV event in Cannes to promote the series.

[55] Speaking of the new series, Gardner commented that "[Torchwood is] taking the Welsh global — retaining the best of British drama while learning all about US production values".

On 19 July 2011 it was announced it had been bought by Eleven, a Network Ten Australia free-to-air digital-only channel,[63] but as of 23 November 2012[update] has not broadcast it.

Other criticisms focused on Jack's relatively minimal role, the unclear direction of the Oswald Danes storyline, the lack of an alien presence in the series, and the show's expectation that the audience care for Rex and Esther, whom they have not had a chance to get to know.

Taking a cultish British programme and giving it a cash injection and a platform for a global audience is a brave move.

Miracle Day, however, ended with several cliffhangers, which Martin found strange in view of its unfavourable reviews and the fact that Davies was not sure he would do any more Torchwood.

[68] Charlie Jane Anders for io9 expressed some continuity concerns that are raised by relating Miracle Day to Doctor Who, the parent show of Torchwood.

As Miracle Day seemingly supposes a catastrophic worldwide phenomenon lasting at least from March to May 2011, it seems quite incompatible with the world of Doctor Who, where in Steven Moffat's 2011 series, companions Amy (Karen Gillan) and Rory (Arthur Darvill) are based in this exact time period without any mention of the problem, or evidence of global catastrophe elsewhere.