Director Lisa Bowerman said: “The script from Gareth is so clever because it’s not only a mysterious, ambivalent science fiction story with Torchwood elements, but it’s a deeply human story, which is touching as well as strange, and I think that’s a very clever combination.

“We were very, very lucky to get Gwyneth Keyworth, and I’ve always been a fan of her work. She has to play this character who turns up twelve years after this child goes missing, and she is actually the child - now an adult, but with a nine-year-old’s mentality. And Gwyneth’s managed to put in this incredible performance that is childlike and sweet and convincing, but also not quite right... I thought she was terribly clever and did it brilliantly.”

Back row; Nia Roberts, Gareth David-Lloyd, Matthew Gravelle. Front; Gwyneth Keyworth