The man found his way quite easily. At every intersection of the ducts luminous code-numbers glowed—"To help us when we make repairs," the man whispered, and laughed. "We use the ducts all the time for spying. I suppose tonight will finish their usefulness, but we'll find some other way."
The underground had known where Thile and Kara were prisoned almost as soon as they had been put there. Twice the knotted rope was let down and twice gratings were removed and then replaced. Birrel went down after Kara himself and took a second or two to hold her in his arms before he lifted her into the duct.
Some time later, he had no idea how long, they had worked their way down below the level of the building and into a dry conduit that their guide said was left over from an earlier day, before the city was rebuilt. The conduit took them for some distance, and then they climbed a flight of wooden stairs into a cellar, and from there went up into the main room of a modest house, where half a dozen active and hard-faced men sat waiting.
They sprang up when Birrel and the others came in, two or three of them pulling weapons. There was a period of heated conversation, and then one of the men shouted for order and got it.
"Now then," he said, "let's hear about it. You first."
He listened, and the others listened, and all the time they watched Birrel with hatred and distrust.
Impatiently, before the man was through telling why he had not killed the Earthman, Birrel broke in on him to speak to Thile and Kara.
"They showed me something today," he said. "Vannevan and Wolt. A cavern full of armaments—enough to blow Ruun out of the sky as soon as they get the fissionable material they need."
Thile said, "We had an idea there was such a place, but we could never pin it down."
"Neither could we," said the man who seemed to be the leader of the group. He looked hard at Birrel. "It's a mighty well-kept secret."