“I’ll do my best. I’ll let you know when I make a move. Meantime, be a good boy and don’t give those guys with the spearguns an excuse to use you for target practice.”

They were directly above the hemispherical-shaped structure at the hub of the lab complex. Zavala remembered it as the transit module where the airlock for the shuttle vehicle was located. Phelps swam under the transit module, past four minisubmersibles attached to the underside like feeding puppies, then up into a shaft that opened into a round pool at the center of a circular chamber.

Phelps removed his mask and communications unit, and Zavala followed his lead. The guards surfaced seconds later. By then, Phelps and Zavala had used a ladder on the side of the pool to climb out. The guards emerged from the pool, and all four men hung their air tanks and gear on wall hooks. The guards took their masks off to reveal hard Asian faces. They put the spearguns aside and produced machine pistols from their waterproof backpacks.

Phelps pressed a switch and a door slid open. He led the way along a tube-shaped corridor to another door that opened into a small room. Phelps told the guards to wait in the passageway, and then he and Zavala stepped inside.

Half of one wall was made of glass, allowing a view of a laboratory containing several workers dressed in white biohazard suits. The workers looked up when Phelps rapped his knuckles on the glass. All went back to work except one, who waved in acknowledgment and disappeared behind a door labeled DECONTAMINATION.

Minutes later, Lois Mitchell stepped into the room. She was wearing a lab coat and slacks, and her raven hair was still damp from the decontamination shower. Despite his predicament, Zavala signaled his appreciation of Lois’s striking good looks with a slight smile. Lois saw it, and the corners of her lips turned up.

“I know you,” she said.

Zavala did a fast mental check of the hundreds of women he had dated through the years and drew a blank.

“Have we met?” he asked cautiously.

Lois laughed.

“I saw you on TV,” she said. “You were the engineer from NUMA who made the dive with Dr. Kane in the bathysphere.” She furrowed her brow. “What on earth are you doing here?”

“I could ask you the same thing,” Zavala said.

Phelps said, “Dr. Mitchell, this is Joe Zavala from NUMA.”

“Lois,” the scientist amended, extending her hand.

“Hate to break up this party,” Phelps said, “but things are moving fast, Dr. Mitchell. My boss is on his way to the lab. My guess is that he wants to check on your project.”

“Actually,” she said, “he’s coming to get the vaccine.”

Phelps narrowed his eyes.

“What do you mean?” he asked.