Jacques Deza has been told he has a gift: he can see through people; guess just from their faces what will become of them. When he encounters the enigmatic Bertram Tupra at a party, Deza is persuaded to join a mysterious underground group. His task: to observe an assortment of people - politicians, celebrities, seemingly ordinary citizens - and predict their next move. But where will Deza's descent into this twilight world eventually take him? The first part of Javier Marias' masterly trilogy asks how well we truly know and understand those around us.