The LAPD find a man dead at home. Nothing suggests foul-play but elements of the victim's house show that something is deeply wrong.
Meanwhile, in Glasgow, DI Rachel Narey is searching for a missing young woman – and the man she suspects of killing her.
When a feed broadcasting the slow and painful death of a final victim is discovered, these two cases become linked.
There's no way to identify him.
No way to find him
No way to save him.
Not without the cooperation of a killer.
And the only way he will cooperate is if he can watch him die