The eighth action-packed installment in a series about a young team of time travelers, this narrative continues to utilize the highly visual 'movie-book' format that has proven to engage reluctant readers. Recognizing the image of a man they've seen in previous time-jumps, the Time Soldiers become keenly interested in a Leonardo da Vinci sketch they see hanging in a local museum. Attached to the portrait is a note alluding to the glowing green stones and a danger that surrounds them, but the key information is lost due to a tear in the note. Traversing back to the Renaissance era to find da Vinci, the adventurers work to discover the truth about these dark dangers and the mysterious traveling man before it is too late. Offering an increased word count from previous selections in the series, this tale utilizes a stealth literacy approach to improving the reading abilities of disinclined students.