'Tess Stimson is the master of the didn't-see-that-coming twist' LISA JEWELL

The brand new suspense thriller from the Sunday TImes and USA Today bestseller.

Could you sacrifice one life to save many? What if that life was your son's?

This year, for the first time, the high school prom will be held on a luxurious cruiser on the lake. Sisters Amy and Iris are excited to be chaperones at the event, seeing their sons all dressed up. It's a proud moment.

But, tonight, the boat will sink.

And as darkness falls, secrets unravel and the air starts to run out, one of the sisters will be forced to make a split-second decision - to save her own son and let her nephew and twenty-one other teenagers drown.

And then, a year later, one of the teenagers will wake up from her coma, ready to tell everyone what really happened at the bottom of the lake. And someone needs to keep her quiet - for good.

A pulse-pounding novel of small-town secrets, lies and betrayal - with a twist you won't see coming.