After collecting their bags at Reagan, they took a cab across the tarmac to their father’s hangar. Letting themselves in, they stored their bags and cleaned themselves up in the loft apartment.

“You think Dad would mind if we borrowed one of his cars to run to the office?” Summer asked.

“He’s always given us a standing offer to drive what we like,” Dirk said. He pointed to a silver-and-burgundy roadster parked near a workbench. “He said in an e-mail before he left for the Pacific that he just got that Packard running strong. Why don’t we take it?”

He checked to see that it had plenty of gas while Summer opened a garage door. Sliding into the driver’s seat, he pulled the choke and adjusted the throttle lever mounted on the steering wheel and hit the starter button. The big straight-eight engine murmured to life. Letting it warm up for a moment, he pulled the car outside and waited for Summer to lock the hangar.

She jumped into the passenger seat with a travel bag in tow, not noticing a white van parked across an adjacent field. “What’s with the funky seats?” she asked.

The Packard roadster’s tight cockpit held two rigid seats. Summer’s passenger seat was permanently offset a few inches farther from the dash than Dirk’s driver’s seat.

“More room for the driver to turn and shift at high speed,” Dirk explained, pointing to the floor-mounted gear lever.

“I’ll gladly take the extra legroom.”

Built in 1930, the Model 734 Packard chassis carried one of the factory’s rarest bodies, a sleek boattail speedster. The trunk line tapered to an angular point, giving the car a highly streamlined appearance. Sporting dual side-mounted spare tires, the body gleamed with metallic pewter paint, contrasted by burgundy fenders and a matching body-length stripe. Narrow Woodlite headlights on the prow, combined with an angled windshield, added to the sensation that the car was in motion even while parked.

Dirk drove north onto the George Washington Parkway, finding that the Packard loped along easily with the highway traffic. It was only a ten-minute drive to the NUMA headquarters, a tall glass structure that bordered the Potomac. Dirk parked in the underground garage, and they took an employee elevator to the top floor and Rudi Gunn’s office. His secretary directed them to the computer resource center, so they dropped down three flights to the high-tech lair of Hiram Yaeger.

They found Gunn and Yaeger parked in front of a wall-sized video screen, examining satellite photos of an empty sea. With bedraggled hair and circles under their eyes, both looked as if they hadn’t slept in days. But the men perked up at the sight of Pitt’s children. “Glad to have you back,” Gunn said. “You gave us quite a scare when your submersible went missing.”

Summer smiled. “Us, too.”