Human Nature was Paul Cornell's fifth original novel, all having been
Doctor Who stories for
Virgin Publishing, and the thirty-eighth
New Adventure. The plot was developed with fellow New Adventure novelist
Kate Orman and the book was well received on its publication in 1995. Several years later, the revived
Doctor Who television series included several people who had worked on the New Adventures. For his second story for the television series, Cornell adapted his novel. Although most praise for the script was directed at Cornell, a great deal of the episode had in fact been rewritten by executive producer
Russell T Davies. Despite
Julie Gardner's position as
executive producer since "
Rose", this episode marks the first time since
Verity Lambert's
1965 swansong, "
Mission to the Unknown", that a woman was the credited
producer of an episode of
Doctor Who. However, it is not producer
Susie Liggat's first production job in the
Doctor Who universe: in 2006, she produced
Invasion of the Bane, the first episode of
The Sarah Jane Adventures. Thus, only she and
John Nathan-Turner have produced episodes from two different programmes set in the
Doctor Who universe. The physical prop of John Smith's journal notebook was created by artist Kellyanne Walker, and incorporates text provided by writer
Paul Cornell. Much of the episode was filmed at
St Fagans National History Museum, an open-air museum near
Cardiff, and
Treberfydd, the Victorian Gothic mansion which served as Farringham School, located near
Llangorse Lake in south Wales. Other interior locations were filmed at Llandaff Cathedral, Cardiff. The Doctor's list of 23 directives, much of which is sped through in the episode, is presented at normal speed in a
deleted scene released on the BBC DVD. In place of the nonexistent unheard requests, David Tennant breaks the
fourth wall to speak about a love for
The Housemartins and also talk nonsense to pad out the time before returning to character for the 23rd and final directive. Another instruction, about not letting Smith eat pears, appears in both the deleted scene and in the novel
Human Nature. ==Reception==