Torchwood creator, and former Doctor Who producer, Russell T. Davies has ruled out the possibility of the Doctor appearing in the spin-off.
Russell T. Davies dismissed the possibility of the Doctor appearing in an episode of Torchwood, the more adult spin-off from Doctor Who. Speaking at the UK launch for Torchwood: Miracle Day the creator of the spin-off revealed its more adult nature ruled out the Time Lord from crossing over and appearing in it.
"No, because actually the Doctor's never gone into Torchwood, it's always been the other way round, Torchwood's gone into Doctor Who, which I think is correct because there's a big child audience for Doctor Who and I think that would demand if we took the Doctor into Torchwood it would be a clash of styles.” - Russell T. Davies
Davies has previously ruled out an appearance by the Doctor in the Torchwood spin-off from similar reasons. However, there have been crossovers with Doctor Who before; in the second series of Torchwood Law & Order: UK the character of Martha Jones (Freema Agyeman) appeared in three episodes. The actress was due to appear in Torchwood: Children of Earth but this planned appearance never happened possibly because of her role in.
The season four finale of Doctor Who featured the Torchwood characters of Gwen Cooper (Eve Myles) and Ianto (Gareth David-Lloyd) alongside Captain Jack (John Barrowman). The finale also featured a crossover with fellow spin-off series The Sarah Jane Adventures which aired on the CBBC Channel and starred Elisabeth Sladen.
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