Heartbeat - Season 7 Episode 21 The Enemy Within

Mike and a college student become friendly. She has a Japanese camera, which causes friction between her and an old army friend of Blaketon's who's been having flash backs from the war. He causes a disturbance in the pub and Mike arrests him. Blaketon's friend is mixing up the past with the present and ends up making an attack on Mike and abducting Blaketon and abandoning him on the moors. Mike is then allowed two weeks off work so he takes the student way on holiday with him.