I'm watching it too and it is quite deep. I'm using the hairstyles to tell what year they're in. I'm not 100% sure but I think the young girl is the sister of one of the members of the Romanian smuggling gang. The undercover police officer sent to cover them befriended her, was rumbled and then had his throat slashed on the seat at the railwaystation.
She was a drug addict and the french policeman, whose own daughter has battled drug problems 'saved her', put her through cold turkey and brought her out the other side. She is a teacher now. She had her throat slashed, I think, because she was also rumbled for talking. Garrett, the man with the boat was not killed as we see him, with his wife, on the boat in the Indian Ocean. The bit that confused me was when, last night, Victor Bourg visited Garrett's wife on both the boat and what looked like a hospital. I think she has a guilty secret! (my theory at the moment, is that she has done something to little Oliver Hughes so that her husband could not get to him - far fetched I know!) I also dont trust the British liaison officer who Emily Hughes is with in the present day. That's my interpretation and I may be completely wrong, but enjoying it anyways. I like to play detective.
