The ship rested in about two feet of water. Around it the whole world curved up to the horizon in a shallow concave sweep like the inside of a great rusty bowl, lined with knee-high reeds that grew as far as the eye could see out of a knee-deep marsh. A fist-sized sun hung low in the sky, its glare dulled to a muddy crimson by a shimmering cloud of gnats that whirled and danced to infinity. There was a sort of vast, featureless roaring in the background that sounded like Niagara at two hundred yards, not deafening but loud enough to force Colonel Sanderson to raise his voice. "The frog noise is worst," he was saying. "It drives us to the point of insanity at times.... One member of our party has succumbed to it already, a machinist named Willkins who disappeared two weeks ago. Apparently the poor fellow drowned himself in the marsh, since no trace of him has been found since." That was when I realized why the little man on the stool beside me looked so familiar--because I had seen his pictures in the papers, along with the rest of Sanderson's crew, a thousand times during the past year. The mixed expression on his face made sense now, too; he wasn't only disgusted and defensive, he was _guilty_. "So that's how you knew what it was like," I said. "You couldn't stick it out with the others, so you jumped ship. You deserted!" He gave me a hangdog look. "It's not deserting unless the country is at war," he said. "It's just going over the hill, A.W.O.L." The television roar got louder, and when I looked up the ship's cameraman was doing a close-up for our benefit. He panned the shot downward until we seemed to be standing ten feet above the marsh, and at that distance I could see plainly what it was that caused the uproar. The water between the reddish-brown reeds was thick with huge frogs, all blinking and croaking like mad. I remember thinking then that you couldn't really blame a man for jumping ship in a hole like that. It was bad enough to be stuck thirty-odd million miles from home, so far that light itself needed three minutes to-- "Hey, wait up!" I said to the little guy, who was sneering at himself in the mirror again. "If you went A.W.O.L. up there, then how the hell did you get back _here_?" I didn't find out. The guy was gone. He had been standing there so close I could have touched him, but now he was gone. I looked around quick. Nobody else seemed to have noticed. All eyes were on the TV screen. Then I saw it. On the floor. Two wet marks--right where the guy should have been, where he _was_. Two wet marks that had a funny shape to them--web-like. I felt my throat tighten at the thought. I shook my head. What was going through it was fantastic, impossible and downright lunacy. There was an intelligent life-form on Mars--beings that looked like frogs and could teleport. Could they also mimic human shape temporarily? Especially if they got hold of one for a model--say a missing crewman....