<P> In 2010, Fellowes hired Alastair Bruce, an expert on state and court ritual, as historical adviser . Bruce explains his role as being "here to guide the production and particularly the director as they bring Julian's words to life . That also involves getting the social conduct right, and giving actors a sense of surety in the way they deliver a performance ." Actor Jim Carter, who plays butler Carson, describes Bruce as the series "etiquette watchdog", and the UK's Daily Telegraph finished its 2011 profile of Bruce's role stating "Downton's authenticity, it seems, is in safe hands ." However, historian Simon Schama criticised the show for historical inaccuracies and "pandering to clichés". Producer Gareth Neame defended the show, saying, "Downton is a fictional drama . It is not a history programme, but a drama of social satire about a time when relationships, behaviour and hierarchy were very different from those we enjoy today ." </P> <P> A "tremendous amount of research" went into recreating the servants' quarters at Ealing Studios because Highclere Castle, where many of the upstairs scenes are filmed, was not adequate for representing the "downstairs" life at the fictional abbey . Researchers visited nearly 40 English country houses to help inform what the kitchen should look like, and production designer Donal Woods said of the kitchen equipment that "Probably about 60 to 70 per cent of the stuff in there is from that period ." Mrs Beeton's Book of Household Management is an important guide to the food served in the series, but Highclere owner, and author of Lady Almina and the Real Downton Abbey: The Lost Legacy of Highclere Castle, Lady Carnarvon, states that dinner parties in the era "would have been even more over the top" than those shown . Lady Pamela Hicks agreed, stating that "it is ridiculous to think that a weekend party would consist of only fourteen house guests, it would have consisted of at least 40!" However, Carnavon understood the compromises that must be made for television, and adds, "It's a fun costume drama . It's not a social documentary . Because it's so popular, I think some people take it as historical fact ." </P> <P> Previously available on Netflix, since 2013 the series has been available only on Amazon Video . </P> <Table> <Tr> <Th_colspan="2"> Title </Th> <Th_colspan="2"> Number of discs </Th> <Th> Year (s) </Th> <Th> Number of episodes </Th> <Th> Release date (UK only) </Th> </Tr> <Tr> <Th> Blu - ray </Th> <Th> DVD </Th> </Tr> <Tr> <Td> </Td> <Td> Complete Series One </Td> <Td> </Td> <Td> </Td> <Td> </Td> <Td> 7 </Td> <Td> 8 November 2010 </Td> </Tr> <Tr> <Td> </Td> <Td> Complete Series Two </Td> <Td> </Td> <Td> </Td> <Td> 2011 </Td> <Td> 8 </Td> <Td> 7 November 2011 </Td> </Tr> <Tr> <Td> </Td> <Td> Complete Series One and Two </Td> <Td> 5 </Td> <Td> 7 </Td> <Td> 2010--11 </Td> <Td> 15 </Td> <Td> 7 November 2011 </Td> </Tr> <Tr> <Td> </Td> <Td> Christmas at Downton Abbey </Td> <Td> </Td> <Td> </Td> <Td> 2011 </Td> <Td> </Td> <Td> 26 December 2011 </Td> </Tr> <Tr> <Td> </Td> <Td> Complete Series Three </Td> <Td> </Td> <Td> </Td> <Td> 2012 </Td> <Td> 8 </Td> <Td> 5 November 2012 </Td> </Tr> <Tr> <Td> </Td> <Td> Complete Series One - Three & Christmas at Downton Abbey </Td> <Td> 9 </Td> <Td> 11 </Td> <Td> 2010--12 </Td> <Td> 24 </Td> <Td> 5 November 2012 </Td> </Tr> <Tr> <Td> </Td> <Td> A Journey to the Highlands </Td> <Td> </Td> <Td> </Td> <Td> 2012 </Td> <Td> </Td> <Td> 26 December 2012 </Td> </Tr> <Tr> <Td> </Td> <Td> Complete Series Four </Td> <Td> </Td> <Td> </Td> <Td> 2013 </Td> <Td> 8 </Td> <Td> 11 November 2013 </Td> </Tr> <Tr> <Td> </Td> <Td> Complete Series One - Four & Christmas at Downton Abbey and A Journey to the Highlands </Td> <Td> 13 </Td> <Td> 15 </Td> <Td> 2010--13 </Td> <Td> 33 </Td> <Td> 11 November 2013 </Td> </Tr> <Tr> <Td> </Td> <Td> The London Season </Td> <Td> </Td> <Td> </Td> <Td> 2013 </Td> <Td> </Td> <Td> 26 December 2013 </Td> </Tr> <Tr> <Td> </Td> <Td> Complete Series Five </Td> <Td> </Td> <Td> </Td> <Td> 2014 </Td> <Td> 8 </Td> <Td> 17 November 2014 </Td> </Tr> <Tr> <Td> </Td> <Td> Complete Series One - Five & Christmas at Downton Abbey, A Journey to the Highlands and The London Season </Td> <Td> 16 </Td> <Td> 19 </Td> <Td> 2010 - 14 </Td> <Td> 42 </Td> <Td> 17 November 2014 </Td> </Tr> <Tr> <Td> </Td> <Td> A Moorland Holiday </Td> <Td> </Td> <Td> </Td> <Td> 2014 </Td> <Td> </Td> <Td> 26 December 2014 </Td> </Tr> <Tr> <Td> </Td> <Td> Complete Series Six </Td> <Td> </Td> <Td> </Td> <Td> 2015 </Td> <Td> 8 </Td> <Td> 16 November 2015 </Td> </Tr> <Tr> <Td> </Td> <Td> Complete Series One - Six & Christmas at Downton Abbey, A Journey to the Highlands, The London Season and A Moorland Holiday </Td> <Td> 19 </Td> <Td> 23 </Td> <Td> 2010 - 15 </Td> <Td> 51 </Td> <Td> 16 November 2015 </Td> </Tr> <Tr> <Td> </Td> <Td> The Finale </Td> <Td> </Td> <Td> </Td> <Td> 2015 </Td> <Td> </Td> <Td> 26 December 2015 </Td> </Tr> </Table>

How many seasons are there of downton abbey on netflix
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