The grownups are out-of-town, and for Charley Decker that means one thing: a last epic weekend with her older brother Greg before he leaves for college. Bring on the burgers, milkshakes, and movie marathons! So when Greg ditches Charley for a date night downtown, she’s kind of crushed. Worse, he gets their mom's boyfriend’s super-expensive, super-rare Mustang towed and needs Charley’s help to get it back. What's an unsupervised seventh grader to do? Grab her best friends, sneak into the city, pull off the ultimate car heist, and then make Greg pay, of course! Only now the Mustang has a new feature in the trunk: a stowaway named Mitch who’s guarding a world-changing secret. And a pair of seriously big, seriously scary dudes are after him. What follows is an all-night race around the clock as Charley and her friends try to dodge the twin terrors, save Mitch, fix a sibling squabble...and get the Mustang home before morning!