In a city full of wonder, a boy and his robot uncover a mystery that could change everything.
Ten-year-old Theo Roman has just moved to Optima City, the smartest city in America.
But almost immediately, he notices something strange. Robots with unusual antennas keep appearing wherever he goes.
At first, Theo doesn't think much of it. Then the city’s machines begin behaving in ways they shouldn’t.
With the help of H.E.R.O., his A.I. robot , Theo starts searching for answers.
And in a city where everything is connected, the smallest clues can lead to a much bigger mystery.