As new allies and old enemies circle, and the days and nights bleed into each other, even the legendary detective struggles to keep his head. That is, until a murder at midnight in a locked cell presents a new mystery. They say old habits die hard… However, this is a case where the prisoners and the guards are all suspects, and everyone has something to hide. With no badge, no authority and no safety net, Rebus walks a tightrope – with his life on the line.