This is one of the better 'animals on the rampage' type of movie. It all starts when a college professor is killed by the hybrid bats he is breeding and the bats escape. These creatures not only drink blood but eat flesh. Soon, other people are being attacked. But it turns out that these people are being targeted. The bats are trained to respond to certain sounds--and when they hear a particular sonic call they kill. Tracey Nelson is very good in the part of the detective. This movie reminded me of THE FLYING SERPENT and THE BAT in that the animals are controlled by a human. Worth checking out.