Watch Bats for Free: How to Stream the Movie Online at 123Movies. . An alien virus that once wiped civilizations out in ancient times through out time has returned overnight by a mysterious thunderstorm infecting all the bats in the area causing them grow into grotesque giant carnivore man-eater monster bats and it's up to humankind to fight for their lives to survive or history will once again repeat it's self as it has thousands of years ago.