Joe mentally kicked himself. The Chief had said he was going to swim. Now—but only now—Joe looked to see what he was doing.

He was far out from shore, swimming unhurriedly to the powerhouse at the middle of the dam. He would reach it, and swing up the ladder that could just be seen going down the lake side of the dam’s top, and he would explain the situation on shore. A telephone call to Bootstrap would bring security men rushing at eighty miles an hour, and parachute troopers a good deal faster. But even before they arrived the Chief would lead the powerhouse crew ashore armed with the shotguns they kept for shooting waterfowl in and out of season.

The men on shore might or might not consider the Chief’s swim to be proof that he knew their intentions. They were probably discussing the matter in some agitation right now. But they couldn’t know that the party on the semi-island was armed.

Suddenly Mike said crisply: “We’re goin’ to have visitors.”

He lay down carefully on the ground, fifteen feet uphill from Sally, where he could look over the ridge. He snuggled the .22 target rifle professionally to his shoulder. He drew a bead.

Three men very casually strolled out of the brushwood on the shore. They moved nonchalantly toward the strand of rocks that led out to the picnic spot. They looked like anybody else from Bootstrap. Casual, rough work clothing.... Haney bent down and picked up four good throwing stones. His expression was pained.

Joe said: “We’ve got pistols, Haney, and Sally’s a good shot.”

The men came on. Their manner was elaborately casual. Joe stepped up into view.

“No visitors!” he called. “We don’t want company!”