to let him in, Murgatroyd," observed Calhoun. "In war time, a man is expected to be polite to anybody with a weapon capable of blowing him up. It's one of the laws of war." He opened both the inner and outer lock doors. The glow from inside the ship shone out on white, untrodden snow. Calhoun stood in the opening, observing that as his breath went out of the outer opening it turned to white mist. "My name is Calhoun," he said curtly to the single dark figure still approaching. "Interstellar Medical Service. A neutral, a noncombatant, and at the moment very much annoyed by what has happened!" A gray-bearded man with grim eyes advanced into the light from the opened port. He nodded. "My name is Walker," he said, as curtly. "I suppose I'm the leader of this military expedition. At least, my son is the leader of the ... ah ... the enemy, which makes me the logical man to direct the attack upon them." Calhoun did not quite believe his ears, but he pricked them up. A father and son on opposite sides would hardly have been trusted by either faction, as warfare used to be conducted. And certainly their relationship would hardly be a special qualification for leadership at any time. He made a gesture of invitation, and the gray-bearded man climbed the ladder to the port. Somehow he did not lose the least trace of dignity in climbing. He stepped solidly into the air lock and on into the cabin of the ship. "If I may, I'll close the lock-doors," said Calhoun, "if your men won't misinterpret the action. It's cold outside." The sturdy, bearded man shrugged his cape-clad shoulders. "They'll blast your ship if you try to take off," he said. "They're in the mood to blast something!" With the same air of massive confidence, he moved to a seat. Murgatroyd regarded him suspiciously. He ignored the little animal. "Well?" he said impatiently. "I'm Med Service," said Calhoun. "I can prove it. I should be neutral in whatever is happening. But I was asked for by the planetary government of Phaedra. I think it likely that your ships come from Phaedra. Your grid ship, in particular, wouldn't be needed by the local citizens. How does the war go?" The stocky man's eyes burned. "Are you laughing at