Ever received a call from an unknown number and they didn't leave voicemail? Chances are you called back - just in case it was an old friend or maybe your boss using a personal cell phone - but instead got roped into an annoying sales pitch (or worse). Phone detective enables you to do a reverse lookup on any 10 digit US phone number; just say phone detective followed by an area code and phone number. While not every phone number is listed, our data is high quality - sourced from the same system used by major telecom carriers.