Casually, Devereaux raised a hand to his cheek and pressed the stud under the skin, just below his right cheekbone. His Mossad-issue right eye increased its impressions-per-second ratio by five hundred percent. He rubbed at his left eye, as if it were tired, closing it so only the right took impressions. Details normally lost to the human eye showed up in his prosthetic perception: a flicker of fear in Sackville-West, the expression flashing through the face so rapidly Devereaux would have been unable to see it without the implant.