Six months later, Luna stood in the laboratory of the Chen-Winters Initiative, watching through the observation window as Helena and her team ran their final tests. The energy storage device—the one based on their father's original research—was ready for its first public demonstration.

"Nervous?" Grayson asked, coming to stand beside her.

"Terrified," Luna admitted. "What if it doesn't work? What if we've built this whole company on something that can't deliver?"

"It'll work. ...