<Table> Christmas special <Tr> <Th> No . overall </Th> <Th> Episode </Th> <Th> Directed by </Th> <Th> Written by </Th> <Th> Original air date </Th> <Th> UK viewers (millions) </Th> </Tr> <Tr> <Th> 34 </Th> <Td> Christmas special </Td> <Td> Juliet May </Td> <Td> Heidi Thomas </Td> <Td> 25 December 2015 (2015 - 12 - 25) </Td> <Td> 10.13 </Td> </Tr> <Tr> <Td_colspan="6"> The BBC plan to televise a carol service from Poplar, but Shelagh's plans for the event are thrown into chaos when the children's choir she has organised is quarantined due to a measles outbreak . Following an argument, Sister Monica Joan goes missing, and when a body is found in the river the nuns fear the worst . This proves to be a false alarm, however, and the elderly nun is eventually tracked down at the now - abandoned country house which had been her childhood home . A partly - recovered Delia re-enters Patsy's life . </Td> </Tr> </Table> <Tr> <Th> No . overall </Th> <Th> Episode </Th> <Th> Directed by </Th> <Th> Written by </Th> <Th> Original air date </Th> <Th> UK viewers (millions) </Th> </Tr> <Tr> <Th> 34 </Th> <Td> Christmas special </Td> <Td> Juliet May </Td> <Td> Heidi Thomas </Td> <Td> 25 December 2015 (2015 - 12 - 25) </Td> <Td> 10.13 </Td> </Tr> <Tr> <Td_colspan="6"> The BBC plan to televise a carol service from Poplar, but Shelagh's plans for the event are thrown into chaos when the children's choir she has organised is quarantined due to a measles outbreak . Following an argument, Sister Monica Joan goes missing, and when a body is found in the river the nuns fear the worst . This proves to be a false alarm, however, and the elderly nun is eventually tracked down at the now - abandoned country house which had been her childhood home . A partly - recovered Delia re-enters Patsy's life . </Td> </Tr>

How many christmas specials of call the midwife