Throughout human history, they have descended from the sky, bearing wisdom and superior technology or so it's said. Their ships have been apparently caught on film, again and again. According to the thousands of Americans who have been abducted, those devious aliens are snatching citizens of the Earth and doing unspeakable things to them. Are aliens really interfering with human affairs and even interbreeding with us? Examine the most compelling evidence with believers and skeptics alike.