Atlas and Beau's normal lemonade stand suddenly turns extraordinary the moment they meet Joe, a neighbor whose grandfather once designed a real time machine. But when their babysitter runs off with their ice cream and an important machine piece, everything goes wild. The boys, Joe, and the professor race across famous colleges: MIT, Harvard, and Princeton, while trying not to get caught by security, chased by helicopters, or blown up by strange, half-working inventions.
Once assembled, the machine opens a portal to the ancient Amazon, where they discover the world's original secret lemonade recipe. Returning with the secret formula, the boys launch a lemonade empire that turns them into overnight stars. But with fame rising and time travel on their hands, what could possibly go wrong next?
