They will, I have had them zip past my head like a bullet. I have had them hit my kitchen window pretty hard and back when we had a whole bunch, I was at my car and two were chasing each other and zipped past my head. I could feel the flutter off their wings as they passed by. They came out of nowhere.Bonner Ima have to get rid of my wife cause she runs my humming birds off. She says they freak her out because they move to fast lol.