Buffalo Bill experienced relief when his comrade passed from view. All might be well if the outlet from the cellar should not prove to be near the back door of the castle.
He was at this door, expecting to open it and admit Alkali Pete, when a pistol shot rang out, and he knew that his one fear had been realized. The homely scout had passed the cellar outlet, had been seen by Bat Wason, and—the king of scouts ceased to speculate, for another shot was heard, followed by a scream of agony.
Regardless of danger to himself, Buffalo Bill rushed out of doors as Thunder Cloud and his Apaches appeared at the side of the castle.
Alkali Pete was not in sight, but there was the opening into the cellar, and through it the king of scouts rushed just in time to escape a fusillade of bullets from the guns of the Indians.
Once inside, he closed and secured the door. A shot made him drop to his knees. It was dark in the cellar, and he feared that he might have jumped from the frying pan into the fire.
Working himself sinuously around the underground apartment, he listened intently, so as to get the location of his enemy.
To his surprise, all was still about him. He waited a few moments, and then deliberately lighted a match. The flame showed him an empty cellar. The trapdoor in the ceiling was closed, and he was positive that no one had escaped to the room above while he had been in the cellar.
Where, then, was the person who had fired the shot that had whizzed by his head?
He lighted another match, and, walking forward, began a close investigation of the ground. A low exclamation burst from his lips when, in a corner, he beheld an open hole. A third match showed it was the entrance of an underground tunnel, which probably terminated outside of the castle inclosure.
By the tunnel the enemy had gone, and by the tunnel had gone, also, Alkali Pete and the prisoners.