T imothy Valentin found his dates the way so many people find each other nowadays: Hinge. Plenty of Fish. Bumble. Match.com. He had a profile you might swipe right on some dull Tuesday night—well groomed, fit, and happy to meet in a reassuringly public place, like the neighborhood bar. Nothing heavy, nothing untoward. In person, he told tales of his work with the FBI. He was professional, even reassuring, and gentlemanly, insistent on buying the drinks. Except Valentin would then offer just one