Dave Sanchez (aka The Gecko) and his pet gecko (aka Sticky) are back in their fourth dangerous encounter with the dastardly treasure hunter Damien Black! Thirteen-year-old Dave Sanchez is a daytime student, an after-school courier . . . and a secret superhero! So far Dave's been able to juggle his different roles. But in Dave's hands is the scariest package he's ever been asked to deliver. It's a tube, sealed on each end with wax, and addressed to . . . Damien Black. Holy tacarole! He can't just hand over a package to the most devious criminal in the city! Who knows what's in there? So Dave breaks a cardinal rule of mail carriers everywhere--he opens the package. Inside is a small bottle that's labeled: one drop, two at most, tested, works. The potion in this bottle is blue and sparkly and oozy and smelly--but what does it do? Ah, poor Dave. He has opened a Pandora's box of trouble. Your classic can of worms. And as a result, he'll find himself facing off with six-horned goats, terrifying tarantulas, a java-junkie monkey--and, of course, Damien Black.