<P> Luther is a British psychological crime drama television series that premiered on BBC One in the UK on 4 May 2010 . The series centres on DCI John Luther (played by Idris Elba), a highly talented detective working in London to solve a series of high - profile murders . Co-stars include Ruth Wilson as Alice Morgan, Warren Brown as DS Justin Ripley, Steven Mackintosh as DCI Ian Reed, and Saskia Reeves as Det Supt Rose Teller . As the series progresses Nikki Amuka - Bird joins as the recently promoted DCI Erin Gray, and Dermot Crowley is promoted to a starring role as Det Supt Martin Schenk, and Michael Smiley continues portraying Benny Deadhead . </P> <P> As of 22 December 2015, 16 episodes of Luther have aired, concluding the fourth series . A fifth series has been announced with filming due to start in early 2018 . </P> <Table> <Tr> <Th_colspan="2"> Series </Th> <Th_colspan="2"> Episodes </Th> <Th_colspan="2"> Originally aired </Th> </Tr> <Tr> <Th> First aired </Th> <Th> Last aired </Th> </Tr> <Tr> <Td> </Td> <Td_colspan="1"> </Td> <Td_colspan="2"> 6 </Td> <Td_colspan="1"> 4 May 2010 (2010 - 05 - 04) </Td> <Td> 8 June 2010 (2010 - 06 - 08) </Td> </Tr> <Tr> <Td> </Td> <Td_colspan="1"> </Td> <Td_colspan="2"> </Td> <Td_colspan="1"> 14 June 2011 (2011 - 06 - 14) </Td> <Td> 5 July 2011 (2011 - 07 - 05) </Td> </Tr> <Tr> <Td> </Td> <Td_colspan="1"> </Td> <Td_colspan="2"> </Td> <Td_colspan="1"> 2 July 2013 (2013 - 07 - 02) </Td> <Td> 23 July 2013 (2013 - 07 - 23) </Td> </Tr> <Tr> <Td> </Td> <Td_colspan="1"> </Td> <Td_colspan="2"> </Td> <Td_colspan="1"> 15 December 2015 (2015 - 12 - 15) </Td> <Td> 22 December 2015 (2015 - 12 - 22) </Td> </Tr> </Table> <Tr> <Th_colspan="2"> Series </Th> <Th_colspan="2"> Episodes </Th> <Th_colspan="2"> Originally aired </Th> </Tr>

How many episodes in season 2 of luther
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