“I am not very much interested in your business, Mr. Oberzohn,” she said, “but I want to know why I am being detained here. Surely, if you’re so rich, you do not want to hold me to ransom?” “To ransom?” His forehead went up and down. “That is foolish talk. Did she tell you?” He pointed at the girl, and his face went as black as thunder. “No, I guessed,” said Mirabelle quickly, not wishing to get her companion into bad odour. “I do not hold you to ransom. I hold you, lovely lady, because you are good for my eyes. Did not Heine say, ‘The beauty of women is a sedative to the soul’? You should read Heine: he is frivolous, but in his stupidity there are many clever thoughts. Now tell me, lovely lady, have you all you desire?” “I want to go out,” she said. “I can’t stay in this underground room without danger to my health.” “Soon you shall go.” He bowed stiffly again, and shuffled across the floor to the furnace. Behind this were the two baize-covered boxes, and one he lifted tenderly. “Here are secrets such as you should not pry into,” he said in his awkward English. “The most potent of chemicals, colossal in power. The ignorant would touch them and they would explode—you understand?” He addressed Mirabelle, who did not understand but made no answer. “They must be kept warm for that reason. One I take, the other I leave. You shall not touch it—that is understood? My good friend has told you?” He brought his eyes to Joan. “I understand all right,” she said. “Listen, Oberzohn: when am I going out for a walk? This place is getting on my nerves already.” “To-night you shall have exercise with the lovely lady. I myself will accompany you.” “Why am I here, Mr. Oberzohn?” Mirabelle asked again. “You are here because you are in danger,” said Oberzohn, holding the green box under his arm. “You are in very great danger.” He nodded with every word. “There are certain men, of all the most infamous, who have a design upon your life. They are criminal, cunning and wise—but not so cunning or wise as Dr. Oberzohn. Because I will not let you fall into their hands I keep you here, young miss. Good morning.” Again he bowed stiffly and went out, the iron door clanging behind him. They heard him climbing the stairs, the thud of the trap as it fell, and the rumble which Joan, at any rate, knew was made by the cement barrel being rolled to the top of the trap. “Pleasant little fellow, isn’t he?” said Joan bitterly. “Him and his chemicals!” She glared down at the remaining box. “If I were sure it wouldn’t explode, I should smash it to smithereens!” she said. Later she told the prisoner of Oberzohn’s obsession; of how he spent time and money in his search for the vital elixir.