Major Klima confirmed Napoleon's conclusion that the woman was a female THRUSH. In all probability, she was resident at the THRUSH European Center E, otherwise she would not be able to live anywhere in Prague without police registration. He kept the thought to himself and felt almost certain that all efforts to find her would be as futile as was the search for Professor Novak and his daughter.

"You hit your two would-be assailants mighty hard, Mr. Solo," Major Klima added. "They only came round an hour or so ago."

"Did interrogation bring anything to light?"

"Not a thing," the Czech frowned. "They've chosen to remain silent, but will probably change their minds when they've been in the cells long enough—not that this helps us at the moment."

"Any news of the body that walked out of the public mortuary?" Napoleon queried.

"No news," Major Klima grumbled. "We have thoroughly questioned all the mortuary staff, all of them conscientious and reliable people, but no one saw or heard a thing."

"Well, Major, there's not much point in my keeping you any longer," Napoleon said, seeing that with the present unsatisfactory state of affairs the Czech felt somewhat uneasy in his company. "I'll be in touch."

"Please do, and let's hope I have better news next time."

Napoleon checked various possible clues but none led him closer to THRUSH European Center E. His investigations led him all over Prague and he found walking on uneven cobblestones tiring. When he finally returned to his hotel room late evening, he felt the need of a hot bath before food or more work. He was about to step into the hot water when the call-sign of his radio receiver started to bleep. He extracted the gadget from his pocket and opened the receiving channel.

"Napoleon," Illya said.

"Yes, where are you, Illya?"

"In Prague. At the Hotel Paris near Powder Tower."

"Can you come to the Axa Hotel in Poric Street?"

"When?"

"In ten minutes."

Napoleon switched off the receiver and stepped into the bath. The hot water was soothing and he wished Illya wasn't coming so soon—he would have liked a long, long soak.

Illya arrived and looked with envy at his colleague now sitting in his room in a comfortable dressing gown. "Some people seem to have all the luck," he said with a grin.

"The THRUSH Center can't be too far away from where I lost contact with the direction finder," Illya explained after a while. "I'll double-check the whole area on both banks of the Moldau to find a lead to their Headquarters."

"Let's hope their detection devices haven't discovered and silenced the direction finder," Napoleon said.

"I don't think they have," Illya said confidently. "Their devices work on different frequencies to ours."

"I wouldn't rely on it too much."

"Perhaps I shouldn't; but then I'm an optimist." They parted later—and Illya returned to the river bank of the Moldau at the point where the road turned inland sharply, while Napoleon again crisscrossed Prague, hoping to hit on an accidental clue.

The first real break came early that evening.

As Napoleon turned from Prikopy Street into Wenceslas Square, his eyes detected the girl standing at a tram stop. Beside her was the man from the airport reception area. There was no possibility of a mistake—they were in full view and he could see them clearly.

Napoleon dived into the entrance of the corner shop to prevent his being spotted by them. He considered whether to communicate with Major Klima but dismissed the thought and decided to follow the pair himself. If need be, he could always call for the Major's assistance later.

A tram with a trailer carriage drew up at the stop and the two boarded the front vehicle. Napoleon mingled with the dense stream of pedestrians, crossed the street towards the island stop in the middle, and managed to board the trailer unnoticed. From his seat he could see them in the front carriage.

The tram journey dragged on and on until they were out of the inner city and well into the suburbs. The pair in the now almost empty front carriage appeared to be engrossed in their evening papers.

As the tram approached the second stop from the last, he saw them prepare to alight. He swiftly stood up and, about fifty yards from the stop, jumped off the fast-moving vehicle. He had to take the precaution— in this completely deserted suburban street they were almost certain to notice him if he left the trailer at the stop.

While the tram driver reduced speed and brought the vehicle to a halt, Napoleon stepped behind a thick tree on the pavement to conceal himself from view. He was only just in time, for seconds later he saw the man scan every direction, obviously checking.

Napoleon shadowed them from a safe distance as they walked along the empty streets without talking to each other. Not once did they look back to see if they were being followed.

They reached the last house of the built-up area, then continued along a dusty path into the country side. It was now almost pitch dark and there were heavy rain clouds. Napoleon was pleased for this gave him added cover. The darkness was actually an ally.

The pair headed for the Moldau, and climbed down the grass-covered embankment to the river shore. A sudden break in the clouds bathed the scene in silvery light. Napoleon slid behind a dense bush and watched them walk along the riverbank. It occurred to him that the spot could not be too far from the area where Illya had lost contact with the direction finder on the previous night.

Almost as they reached the bend where the Moldau turned in a northerly direction, they stopped. Napoleon's view was obscured by some high foliage, but he heard the sound of a boat being dragged over stony ground, and soon afterwards there came the unmistakable noise of rowing oars. He saw a small boat moving across the river towards the far shore.

Napoleon watched it through his binoculars and was surprised when it stopped alongside an almost vertical rock formation covered with moss and small vegetation. He was even more surprised when he saw a section of the rock slide to one side to enable the boat to enter what was obviously a secret water passage. Immediately the boat had entered, the ingenious stone door shut and the massive rock looked as impenetrable as before.

This must be the way into the THRUSH European Center, he thought. He activated his ultra-shortwave radio transmitter-receiver to give Alexander Waverly this new information, and when Channel D was closed again, walked along the riverbank searching for a boat in which to cross the river.

About half a mile from the spot where the two THRUSH agents had boarded their rowing boat, he found a kayak lying on the grass verge some twenty feet from the river. He lifted the light boat, carried it to the water, boarded it, and steered towards the rock formation on the far bank.

As he reached the rock the clouds began to close in again on the moonlight, but before darkness engulfed him he located a small lever in a crevice beneath a layer of artificial moss. He tried to turn it, without success. Perhaps it was locked by a safety device from the inside? He extracted a small electronic gadget from one of his pockets. It was constructed to open any lock silently.

He was in the process of fastening the opener to the lever when the river currents moved the kayak from the rock. To keep the boat in position, he grabbed the lever with his left hand and unintentionally pulled it. The rock slid aside. The door had been constructed from steel and made to look like a genuine continuation of the moss-covered rock formation.