As the investigation into the murder of Danny ( Oskar McNamara) cNamara) continues, local newsagent Jack Marshall ( David Bradley) ey) is beginning to take up prime position as the No. 1 suspect. His true intentions behind being the head of the sea cadets is questioned. Also now in the firing line is Susan Wright ( Pauline Quirke), who appears s to be hiding something after an old newspaper clipping is found. And nd just to add more into the mix, Reverend Paul Coates ( Arthur Darvill) ) seems to have a secret too. Could his IT lessons for the boys mean he has taught them how to hide important information? And if so, why? With this many people now potentially a killer, r, DI Alec Hardy ( David Tennant, pictured) has his work cut out.