'Terrifyingly timely and provocative' Val McDermid

'The most original crime novel you'll read this year' Clare Mackintosh

In the UK, someone is reported missing every 90 seconds.

Just gone. Vanished. In the blink of an eye.

DCS Kat Frank knows all about loss. A widowed single mother, Kat is a cop who trusts her instincts. Picked to lead a pilot programme that has her paired with AIDE (Artificially Intelligent Detective Entity) Lock, Kat's instincts come up against Lock's logic. But when the two missing person's cold cases they are reviewing suddenly become active, Lock is the only one who can help Kat when the case gets personal.