When 15-year-old Raleigh Harmon finally conquers her worst fear—by trespassing, no less—she can't wait to tell her best friend, a smart-mouthed physics genius named Drew Levinson.

Only Drew’s gone. Really gone. And everybody's insisting she ran away, a claim that skyrockets Raleigh’s suspicions: Drew Levinson is the least impulsive person she knows.

Armed with an encyclopedic knowledge of city criminal codes, one rock hammer, and a stubborn streak as wide as the Chesapeake Bay, Raleigh scours for clues. Too bad even the cops aren't on her side. So was Drew secretly meeting somebody? Escaping her parents, who are total loons? Or is Raleigh’s hunch dead-on: Her best friend didn't choose to leave.

The first mystery in a series, Stone and Spark features Raleigh Harmon, future forensic geologist and formidable Special Agent for the FBI—provided she survives her high school years.