Two missing children. One dead curator. A devious killer who’s one step ahead.

Detective Markham gets a call. His plans for a peaceful Christmas beside the fire are about to go up in flames . . .

Fourteen years ago
Nine-year-old twins Annie and Dominic are playing hide and seek, through the twisty halls of the Tower of London — as someone watches from the shadows. By the time their mum comes looking for them, it’s already too late. The twins have vanished without a trace.

Now
Margaret Esdaile — the Tower’s brilliant curator — thinks she finally knows what happened to Annie and Dominic. She calls Markham’s colleague, promising him a new lead that will blow the case wide open. But she fails to show up to their meeting.

Hours later, Margaret is found dead.

She devoted her life to uncovering the darkest secrets in the Tower’s long and bloody history. Which of them was worth dying for?

It’s up to Markham and his team to find out before history repeats itself . . .