While at a lab one day, Dr. Paul Beecher grabs the wrong pills and takes them home not knowing that they are made from the blood of vampire bats. After mistakenly taking one of the pills, he is instantly addicted and must take one pill every day. Each time he takes a pill he turns into a hairy insane killer, who doesn't remember what he's done, except as a vague dream. Local police and scientists work franticly to try and piece the puzzle together in the hope that they can stop THE VAMPIRE. A.K.A.: IT'S ALWAYS DARKEST BEFORE THE DAWN and MARK OF THE VAMPIRE
This vintage horror flick marries the worlds of DRACULA and DR. JEKYLL & MR. HYDE with a tale about a pill-popping doc who turns into an insane killer on a nightly basis, then forgets all about it the next day. The pills that the deranged M.D. is swallowing are made from the blood of vampire bats, and are hopelessly addictive, leading to a frantic chase by the local villagers and police as they try to stop him before it's too late.