Crawford steered the Miami back and forth across the Russian sub’s track, solving for her course and speed. She seemed to be heading a little east of due north, straight and true with no variation at all. The solution showed her on a course of zero-three-five, traveling at a speed of eight knots. The Akula didn’t seem to be in much of a hurry or to be the least bit suspicious that anyone might be trailing her. She hadn’t changed course or cleared baffles since Miami had detected her twenty-four hours before. That was a very long time for any submariner to go without turning around to try to catch anyone who might be trailing him. It seemed as if the Russian skipper expected someone to be following him.

The pair of boats had left the open water over two hundred miles back. Now there was a thick layer of ice above them, stretching for many miles in every direction. If they needed to go to the surface for any reason, they would have to search for a polynya, a thin place in the ice to break through. In the winter up here, these holes were few and far between.

Crawford grimaced as he rubbed his aching neck. The excitement of the chase had begun to wane hours ago. His blue poopie suit was wilted and sweat-stained and his face felt like coarse sandpaper. He stared into the dregs of his coffee. It had long since gone cold.

Glancing around the control room, Crawford confirmed that everyone else looked as tired as he felt. Andy Gerson sat slouched on a stool in front of one of the fire control computer screens. He was hunched over, talking to Bill Wittstrom. Tired or not, they were trying to refine the solution some more, learning all they could about the unidentified sub.

Bill Schutte looked up from the navigation chart he was using. “Skipper, looks like he’s heading for the north tip of Novaya Zemlya. You don’t think he’s making a transit around to the Pacific, do you?”

Crawford stood, stretched, and stepped over to stand beside the navigator. He looked at the positions of the two subs, Miami and the unknown Russian, on the chart of the Arctic Ocean. Their tracks were on a course to pass just clear of the northernmost tip of that piece of frozen real estate. From there, it was a straight shot past Franz Josef Land, a small archipelago of mostly uninhabited islands at the edge of the permanent pack ice, into the Arctic Ocean, and then to the Bering Straits and the Pacific Ocean.

Crawford scratched the day-old stubble on his chin for a minute, lost in thought.