When the Confederate submarine, HL Hunley, disappeared near the Charleston harbor in 1864, the cause was assumed to be collateral damage from a blast sustained by a larger, nearby ship. But when the sub was raised 131 years later, all eight crew members were still at their posts, their skeletons—and the sub's hull—intact. What happened? Rachel Lance set out to solve the mystery for her PhD thesis, and solve it she did. This is her account of her three-year quest to figure out what other scientists could not.