A really readable novel focusing on a woman, Lucy, whose sister, Nicki, is missing. 
Nicely paced, my only quibble is that the twist felt a little contrived and close to the edge of being unbelievable…I felt as if another layer could have been added to help explain this a little more believably. Still, it held me in its clutches and the chapters told from the POV of the abductor were brilliantly chilling and more than made up for any doubts.