318 Suddenly a Brain appeared in the room. Christian recognized him by the scar on his nose: it was Waldo. He was alone and armed with a decapitation. He saw Christian and raised his hand with the weapon at the moment when Fox pulled the cord.

319 The net fell. Waldo tried to touch the black crystal on his belt, but could not do it because of the net. Christian jumped at Waldo and hit him heavily with his automatic gun. The Brain fell on the floor. Christian unfastened the Brain's belt with the crystal and gave it to Fox.

320 "Go!" he said. "I'll take care of Waldo."

321 Doctor Fox put the belt with its black crystal into a metal box and locked the box. Then he quickly left the room.

322 Christian lit a cigar. Then he lifted Waldo from the floor, threw him over his shoulder and went out. He saw Fox's car in the distance. Reaching the garage, he put Waldo into the other car, got in himself, started the engine and drove off.

Waldo spat.

323 All the way to the hiding-place he spat and cursed Christian - and there were some words in his speech, which Christian did not understand. These words sounded English, but he did not know them.

324 The cellar of the house where Christian brought Waldo was empty. In the middle was a big barrel filled with water. It was very heavy, and Christian tied Waldo to it. In one corner of the cellar there were stone steps, which led to a massive door. Christian had locked this door, and the key was in his pocket.

325 The Brain's decapitator was pushed under Christian's belt. He looked at his prisoner, holding his automatic in his hand.

326 "Listen," he said. "You are going to answer my questions. We are quite alone, and I shall make you talk."

Waldo spat again.

327 Christian lit a cigar and held it close to Waldo's face.

328 "You will be sorry, Christian," said Waldo. "You will answer for it."

329 "Answer me!" said the captain. "I'm losing patience... Where do you come from? How many of you are there? How do your crystals work?"

330 He received no answer. He raised his hand and struck Waldo a heavy blow on his face.

"Talk, I tell you!"

331 He took the Brain's weapon from under his belt and pointed it at him.

332 "I am giving you three minutes," he said. "If you don't speak and answer my questions, I'll use your weapon on you. I'll decapitate you."

333 The telephone began to ring.

334 Christian was surprised. Only Fox knew that he was there. He took the receiver.

"Chris? Fox here. The crystal has disappeared. I kept looking at the box all the way here, and when I unlocked the box just now, it was empty. There was nobody near me. But the belt with the crystal has disappeared!"

335 Somewhere in the south of England a conference was taking place. A group of scientists were sitting and standing round the laboratory table. On the table there were parts of the weapon, which Christian had seized from the Brains and sent to Military Intelligence.

336 The Minister of War was looking at the parts of the weapon attentively.

337 "The weapon worked on quite a new principle," said the leader of the research group. "By some method - we don't understand it - power is taken directly from the atmosphere and changed into heat energy. This heat energy is emitted in a concentrated ray, which annihilates any material form."

The Minister of War thought.

338 "Can we make such a weapon?" he asked.

339 Outside the laboratory there was a strong guard of soldiers. They were ready for a possible attack of the Brains.

340 Suddenly the guard commander saw a great cloud of flame and smoke rising over the laboratory. A few minutes later nothing remained of the laboratory and the people who were inside it.

341 The guard commander sent a telephone message to Downing Street.