<Tr> <Th> </Th> <Td> "Episode 4" </Td> <Td> Michael Crompton </Td> <Td> Marc Evans </Td> <Td> 6.78 </Td> <Td> 11 May 2015 (2015 - 05 - 11) </Td> </Tr> <Tr> <Td_colspan="6"> As Collersdale finally catches up with David and his family, his motive for pursuing them becomes clear and it is down to Robert to save the day, following another attempt to abduct Joe . However, after the family return home, Robert still has an unanswered question regarding the death of witness Susan Reynolds, requiring a visit to her husband in prison and a showdown with the person who betrayed him and Susan . </Td> </Tr> <Table> <Tr> <Th> Episode </Th> <Th> Title </Th> <Th> Directed by </Th> <Th> Written by </Th> <Th> Original airdate </Th> <Th> Viewers (millions) </Th> </Tr> <Tr> <Th> 5 </Th> <Td> "Episode 1" </Td> <Td> Marc Evans </Td> <Td> Ed Whitmore </Td> <Td> 7 September 2017 (2017 - 09 - 07) </Td> <Td> 5.09 </Td> </Tr> <Tr> <Th> 6 </Th> <Td> "Episode 2" </Td> <Td> Marc Evans </Td> <Td> Ed Whitmore, Tracey Malone </Td> <Td> 14 September 2017 (2017 - 09 - 14) </Td> <Td> 4.31 </Td> </Tr> <Tr> <Th> 7 </Th> <Td> "Episode 3" </Td> <Td> Marc Evans </Td> <Td> Ed Whitmore, Tracey Malone </Td> <Td> 21 September 2017 (2017 - 09 - 21) </Td> <Td> 3.85 </Td> </Tr> <Tr> <Th> 8 </Th> <Td> "Episode 4" </Td> <Td> Marc Evans </Td> <Td> Ed Whitmore, Tracey Malone </Td> <Td> 28 September 2017 (2017 - 09 - 28) </Td> <Td> 3.53 </Td> </Tr> </Table> <Tr> <Th> Episode </Th> <Th> Title </Th> <Th> Directed by </Th> <Th> Written by </Th> <Th> Original airdate </Th> <Th> Viewers (millions) </Th> </Tr>

How many episodes are there in safe house 2