Still on their quest to teach TJ Finkelstein the life lessons she'll need to be a great world leader, 23rd-century goofballs Tuna and Herby are brewing up even more trouble for the new kid in Malibu. As the boys try to repair their futuristic gadgets, a little glitch in their Thought Broadcaster Pen lands TJ in the body of her nemesis, TV star Hesper Breakahart . . . and vice versa. And the plot thickens when Tuna and Herby decide to put TJ's new look and superstar power to use. The time stumblers set up a concert for "Hesper" as a diversion while they sneak aboard a nuclear submarine and borrow a plutonium power pack—one of the items needed to fuel their time pod and get them out of TJ's life. Meanwhile, Tuna and Herby are hounded by their own nemesis, Bruce Bruiseabone, who's having a little trouble with forgiveness . . . a lesson that TJ realizes she might also need to learn as she walks a mile in Hesper's shoes—and body!