What are your plans for summer vacation? Chances are they can't compare to the breathless (and yes, humorous) adventures of twin brother and sister Coke and Pepsi McDonald, the stars of The Genius Files: Mission Unstoppable. Released in January by HarperCollins, the novel launches a new series by Dan Gutman. On a cross-country trip with their parents, Coke and Pepsi uncover a secret government plot and must elude some nefarious pursuers, all while taking in offbeat roadside attractions.

"I thought it would be cool to write an action/adventure/mystery/travel/buddy comedy with a plot that involved yo-yos, Pez dispensers, the largest ball of twine in the world—and Spam," Gutman says. Calling this "a heartwarming family story," the author explains that the second installment in the series, due in January 2012, will take Coke and Pep from Wisconsin to "climactic confrontation" in Washington, D.C., with stops along the way at the National Mustard Museum and the duct tape capital of the world.

The author will sign copies of Mission Unstoppable today, noon–1 p.m., at Table 14. At the same autographing session, Gutman will also be signing copies of Ms. Leakey Is Freaky!, the 12th and final title in the My Weird School Daze series from HarperCollins. But fans have nothing to fear: "Wrap things up? Are you crazy?" jokes Gutman. "I'll wrap things up when HarperCollins figures out a way to pry the laptop out of my cold, dead hands."

It looks like things at My Weird School are about to get weirder with the June release of Miss Child Has Gone Wild! and Mr. Harrison Is Embarrassin'!, the debut titles in Gutman's My Weirder School series. And the author hopes there's no end in sight for these wacky stories that make kids laugh. "I hope that My Weird School goes on forever, or at least until my daughter Emma's college education is paid for," he says. "Speaking of which, I got the idea for the series when Emma [now in high school] was in second grade. She was reading Junie B. Jones, and I thought there should be something like Junie B. Jones told by a boy. So I basically ripped off Barbara Park. Shhhh! Don't tell her."

Gutman has not forgotten about the slightly older readers of his Baseball Card Adventures series, either. He's currently hard at work on the next one, about Boston Red Sox great, and war hero, Ted Williams.