This series showed so much promise! An incredible line-up of actors for virtually every character in the story. What a shame the script and the story was such a mess! Every possible scenario for the disappearances was brought up but hardly any of them were resolved clearly. So many good actors included but a lot of the characters seemed pointless. Even the conclusion of the series was messy and only partially clarified. The sound was so poor too! Couldn't hear a lot of the quieter voices properly despite my clinically tested excellent hearing. The script was messy and inadequate. The different characters were confusing. The conclusion was full of holes. I really expected so much better, especially coming from the BBC.