“Maybe.” Austin looked over at Rudi Gunn, who had been listening to the exchange with Captain Atwood. Gunn nodded slightly, like someone bidding at an auction. Do what has to be done. Austin got back to Captain Atwood and said they would try to find the Sea Hunter. Then he relayed the ship's last known position to the pilot. The chopper banked and headed off at a tangent.

Zavala sat up and his eyes snapped open. He had been plugged into a Walkman, completely absorbed in a Latin American CD. Zavala was an experienced pilot who flew by the seat of his pants like an old barnstormer. Sensing the course change, he removed his earphones and peered out the window, a quizzical expression on his face.

“We're making a detour,” Austin said, explaining the situation. Then he called the Argo and asked the captain to advise the Trouts of the change in plan. Paul and Gamay had stayed aboard the ship to map out the sea bottom in the area of the sunken cargo vessel and planned to return to port with the ship in a few days.

Austin closed his eyes and tried to picture the Sea Hunter as he remembered her from two years before, when he had sailed on the research vessel during a survey in the Caribbean. He visualized the vessel as if he were looking at a computer-rendered image. It was a relatively easy task because it was practically identical to the Argo, having been built at the same shipyard in Bath, Maine. The two-hundred-foot-long hull was painted the familiar turquoise hue, like all NUMA research vessels. An A-frame hung over the stem, a hydraulic crane towered over the raised deck behind the I bridge and there was a smaller boom on the starboard side.

A single tapering -funnel stuck out through the roof of the cream-colored bridge superstructure and a tall radio mast rose like a flagpole from the bow. His mental camera floated from the aft deck into the ship, through the winch-operation station, the main lab, library and mess hall. Below this deck would be scientific stores, the lower lab and crew and scientists' accommodations. The ship normally traveled with a crew of twelve and room for a dozen scientists. In the wheelhouse, he could picture the Hunter's good-natured skipper, Captain Lloyd Brewer, a highly competent sailor-scientist who would not have ignored a call from another NUMA vessel.

The pilot flew a dead-reckoning course, following a line between the ship's last-known position and her destination. Austin took a post on one side of the helicopter, and Zavala pressed his nose against a window on the other. Gunn went up to the cockpit to scan the sea ahead. They saw fishing boats, commercial vessels and cruise ships. Sightings thinned as they moved away from the more heavily traveled traffic lanes.

Austin checked his watch and called the pilot on the intercom. “How are we doing?”

“We'll have to turn back pretty soon.”