Friday did not answer. He was guessing at the location of the mechanism within, and trying to summon up all the knowledge he had of such things. After a moment he bent one of the live ends of the wire he was holding into a gentle curve and felt his way down within the lock with it, carefully keeping the other end clear of all contacts. Seconds went by as his fingers delicately worked--seconds that told terribly on Hawk Carse. For the screen was blank and lifeless, and there was no way of knowing how far the work in the laboratory had meanwhile progressed. In his mind remained each detail of the scene as he had viewed it last: the strapped-down figure, the approaching anesthetic cylinder, the knives lying in readiness.... How was he to know if one of those instruments were not already tinged with scarlet? "Oh, be quick!" he cried again. "If I can touch a live part of the lock's circuit," grunted Friday, absorbed, "there ought--to--be--trouble." * * * * * Suddenly currents clashed with a sputtering hiss, and a shower of sparks shot out of the knob-hole and were instantly gone. Short-circuited! It remained to be seen whether it had destroyed the mechanism of the lock. Friday dropped the hot, burned-through wire he was holding and reached for the knob, but the Hawk had leaped into life and was ahead of him. In a moment the knob was in the door and its holding screw part-way in. Gently the Hawk tried the knob. It turned! But they did not leave the cell--then. Ku Sui's voice was echoing through the room, more than a trace of irritation in its tone: "Hawk Carse, you are beginning to annoy me--you and your too-clever black satellite." Carse's eyes flashed to the ceiling. A small disklike object, almost unnoticeable, lay flat against it in one place. "Yes," continued Ku Sui, "I can talk to you, hear you and see you. I believe you have succeeded in destroying the lock. So open it and glance into the corridor--and escape, if you still want to. I rather wish you'd try, for I'm extremely busy and must not be disturbed again." Graven-faced, without comment Carse turned the knob and opened the door an inch. He peeped through, Friday doing so also over his head--peeped right into the muzzles of four ray-guns, held by an equal number of coolie-guards waiting there. "So that's it," Friday said, dejectedly. "He saw me workin' on the lock an' sent those guards here at once. Or else had them there all the time." * * * * * The Hawk closed the door and considered what to do. Ku Sui's voice returned. "Yes," it sounded metallically, "I've an assistant posted here who's watching every move you make. Don't, therefore, hope to surprise me by anything you may do. "Now I am going to resume work. Reconnect the screen: I've had the burned-out fuse replaced. If you won't, I'll have it done for you--and have you so bound that you'll be forced to look at it.