Zero Calling is the story of an ordinary man, David, who is coerced by a mysterious caller, Zero, to do his bidding by 'righting wrongs' in Singaporean society. David quickly realizes what he is doing is no more than gutter vigilantism - taking the law into his own hands. However, David cannot escape from Zero because this mysterious master has made him a slave: Zero knows where he is, what he does and even who he talks to. It seems like Zero also has the power to harm those he holds dear - his wife, Julie, and his teenager step-daughter Maddy, and will not hesitate to do it in the course of playing this twisted game. Through this difficulties, David races with time to find out the identity of Zero so that he can have his life and privacy back. Who is Zero? An enemy from the past? Whoever he is, he has to be unmasked and stopped before he claims another victim - or before the police closes in on David and puts him behind bars.
—Anonymous