Death Dial (1970)

Sinopsis

A devious call center gang mercilessly victimizing people all over the city meets its match when they ring a mysterious medium called Cha Ba, an elderly woman desperate to avenge her dead niece they have previously scammed. A simple scam phone call turns into a bloody vengeance story as Cha Ba, along with another victimized police officer, tracks down the ring that runs the scam ring in the city.