Harry had slightly more luck with his stalking, perhaps because he had more experience sneaking around unobtrusively than he did speaking to strangers. For the most part, Riddle remained unimpeachable, but Harry had caught him extorting a sixth year Slytherin in the library. Under the cover of his invisibility cloak, Harry watched Riddle loom over a girl, expressionless face somehow more menacing than if he were scowling.