H. S. Stone
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Using an old radio that he inherited from his grandfather, Charlie picks up unusual transmissions on a shortwave frequency. Every morning and every evening, a woman’s deep, monotonous voice recites a series of seemingly random numbers. The numbers change every day, and Charlie can’t figure out what they mean.
Enlisting the help of his best friend, Jenny, Charlie tries to unravel the mystery behind the messages. However, the more that he and Jenny dig into the significance of the transmissions, the more that Charlie realizes he has a bigger problem on his hands.