It was on May Day, not all that long ago, though it seems so, that I sat to the rear of the bar at Captain Tony's in Key West, to the right, near to the fireplace, drinking one of my seasonal beers. It was a little after eleven, and I had about decided that this one was a write-off, when Don came in through the big open front of the place. He glanced around, his eyes passing over me, located a vacant stool near the forward corner of the bar, took it, and ordered something. There were too many people between us, and the group had returned to the stage at the rear of the room behind me and begun another set, with a loud opening number. So, for a time, we just sat there, wondering, I guess.

After ten or fifteen minutes, he got to his feet and made his way back to the rest room, passing around the far side of the bar. A short while later, he returned, moving around my side. I felt his hand on my shoulder.

Bill! he said. What are you doing down here?

I turned, regarded him, grinned.

Sam! Good Lord! We shook hands. Then, Too noisy in here to talk, he said. Let's go someplace else.

Good idea.

After a time, we found ourselves on a dim and deserted stretch of beach, smelling the salty breath of the ocean, listening to it, and feeling an occasional droplet.

We halted, and I lit a cigarette.

Did you know that the Florida current carries over two million tons of uranium past here every year? he said.

To be honest, no, I told him.

Well, it does ... What do you know about dolphins?

That's better, I said. They are beautiful, friendly creatures, so well adapted to their environment that they don't have to mess it up in order to lead the life they seem to enjoy. They are highly intelligent, they're cooperative, and they seem totally lacking in all areas of maliciousness. They ...

That's enough, and he raised his hand. You like dolphins. I knew you would say that. You sometimes remind me of one, swimming through life, not leaving traces, retrieving things for me.

Keep me in fish. That's all.

He nodded.

The usual arrangement. But this one should be a relatively easy, yes-or-no thing, and not take you too long. It's quite near here, as a matter of fact, and the incident is only a few days old.

Oh! What's involved?

I'd like to clear a gang of dolphins of a homicide charge, he said.

He expected me to say something, and he was disappointed. I was thinking, recalling a news account from the previous week. Two scuba-clad swimmers had been killed in one of the undersea parks to the east, at about the same time that some very peculiar activity on the part of dolphins was being observed in the same area. The men had been bitten and chewed by something possessing a jaw configuration approximating that of Tursiops truncatus, the bottle-nosed dolphin, a normal visitor and sometime resident of these same parks. The particular park in which the incident occurred had been closed until further notice. There were no witnesses to the attack, as I recalled, and I had not come across any follow-up story.

I'm serious, he finally said.

One of those guys was a qualified guide who knew the area, wasn't he?

He brightened, there in the dark.

Yes, he said. Michael Thomley. He used to do some moonlighting as a guide. He was a full-time employee of the Beltrane Processing people. Did underwater repair and maintenance at their extraction plants. Ex-Navy. Frogman. Extremely qualified. The other fellow was a landlubber friend of his from Andros. Rudy Myers. They went out together at an odd hour, stayed rather long. In the meantime, several dolphins were seen getting the hell out, fast. They leaped the 'wall,' instead of passing through the locks. Others used the normal exits. These were blinking on and off like mad. In a matter of a few minutes, actually, every dolphin in the park had apparently departed. When an employee went looking for Mike and Rudy, he found them dead.

Where do you come into the picture?

The Institute of Delphinological Studies does not appreciate the bad press this gives their subject. They maintain there has never been an authenticated case of an unprovoked attack by a dolphin on a human being. They are anxious not to have this go on record as one, if it really isn't.

Well, it hasn't actually been established. Perhaps something else did it. Scared the dolphins, too.

I have no idea, he said, lighting a cigarette of his own. But it was not all that long ago that the killing of dolphins was finally made illegal throughout the world, and that the pioneer work of people like Lilly came to be appreciated, with a really large-scale project set up for the assessment of the creature. They have come up with some amazing results, as you must know. It is no longer a question of trying to demonstrate whether a dolphin is as intelligent as a man. It has been established that they are highly intelligent, although their minds work along radically different lines, so that there probably never can be a true comparison. This is the basic reason for the continuing communication problems, and it is also a matter of which the general public is pretty much aware. Given this, our client does not like the inferences that could be drawn from the incident, namely, that powerful, free-ranging creatures of this order of intelligence could become hostile to man.

So the Institute hired you to look into it?

Not officially. I was approached because the character of the thing smacks of my sort of investigation specialties as well as the scientific. Mainly, though, it was because of the urgings of a wealthy little old lady who may someday leave the Institute a fortune: Mrs. Lydia Bames, former president of the Friends of the Dolphin Society, the citizen group that had lobbied for the initial dolphin legislation years ago. She is really paying my fee.

What sort of place in the picture did you have in mind for me?

Beltrane will want a replacement for Michael Thomley. Do you think you could get the job?

Maybe. Tell me more about Beltrane and the parks.

Well, he said, I guess it was a generation or so back that Dr. Spencer at Harwell demonstrated that titanium hydroxide would create a chemical reaction that separated uranyl ions from seawater. It was costly, though, and it was not until years later that Samuel Beltrane came along with his screening technique, founded a small company, and quickly tamed it into a large one, with uranium-extraction stations all along this piece of the Gulf Stream. While his process was quite clean, environmentally speaking, he was setting up in business at a time when public pressure on industry was such that some gesture of ecological concern was pretty much de rigueur. So he threw a lot of money, equipment, and man-hours into the setting up of the four undersea parks in the vicinity of the island of Andros. A section of the barrier reef makes one of them especially attractive. He got a nice tax break on the deal. Deserved, though, I'd say. He cooperated with the dolphin studies people, and labs were set up for them in the parks. Each of the four areas is enclosed by a sonic 'wall', a sound barrier that keeps everything outside out and everything inside in, in terms of the larger creatures. Except for men and dolphins. At a number of points, the 'wall' possesses 'sound locks', a pair of sonic curtains, several meters apart, which are operated by means of a simple control located on the bottom. Dolphins are capable of teaching one another how to use it, and they are quite good about closing the door behind them. They come and go, visiting the labs at will, both learning from and, I guess, teaching the investigators.

Stop, I said. What about sharks?

They were removed from the parks first thing. The dolphins even helped chase them out. It has been over a decade now since the last one was put out.