It's just another day for New York City subway dispatcher Walter Garber, until Ryder, a bitter ex-con, hijacks one of the trains. Unless the city pays Ryder one million dollars within the hour for each hostage on the train, he and his four armed accomplices will execute them all. The mystery is: where does Ryder plan to go once he gets the money? Garber finds himself in an unlikely position of power, since he is the only one who knows the subway system well enough to foil Ryder's plans.