When Anna Matheson fails to collect her son from the babysitter after a works party, the police are swiftly called. Anna is a stickler for time and a good mother - she would never abandon her baby. Her disappearance is totally out of character and DI Isabel Blood and her team soon suspect foul play. CCTV footage shows Anna was last seen at precisely 11.11pm, as she collected her coat to leave the party. But the cameras outside the venue have failed to pick up her exit from the car park - how could she have vanished in plain sight? Rumour has it that Anna was set to make big changes in the workplace, and Isabel can't help but think someone wanted her out of the way. Everyone at the party is a suspect, and all the clues point to murder...