Suffer little children.
The detective works in the Human Trafficking Unit and these are unknown children who have been smuggled into the country and disappeared.
This hard-hitting story follows Carter (played by Damian Lewis) as he tries to save just some of the faces on his wall, such as Rosemary, an 11-year-old girl from West Africa who is sold on as a servant.
"It's an extraordinarily moving story," says Damian. "It's inconceivable that this happens under our noses, yet it does. It's both shocking and emotional."
HARD-HITTING: Damian Lewis with co-star Wunmi Mosaku