The lead turned out to be accurate. The Ghosts’ dangerous project was unfolding in the heart of a red giant star — concealing their work from the Xeelee, and, incidentally, from us.

The disastrous outcome of that project all but destroyed us.

After that, human surveillance of Ghost quagma projects was stepped up.

And now it seemed that the Ghosts were at it again.

The Sink Ambassador said, “You do not understand, Jack Raoul.”

“Oh, don’t I?”

“This is a new program, of great significance. We have every right to progress it, unhindered. Now.” It suddenly turned hospitable. “You have traveled a long way. Your doctor is on hand. Perhaps you wish to rest, before returning to the plane of the Galaxy—”

I approached it, holding my arms out wide, my silvered hands raised like weapons. I hoped that the Ghosts — the Sink Ambassador at any rate — had studied humans sufficiently to get something out of my body language. “Sink Ambassador, we’re not going to let this go. We have to know what you’re doing, out here.” I pushed my sculptured face so close to its silvery hide I could see my own distorted reflection. “After last time, we’re quite prepared to use force.”

It seemed to stiffen; I tried to read the thin tones of the translator chips. “Is this some formal declaration of—”

“Not at all,” I said. “Our communications are secure, right now. This is just you, and me, out here in the halo of the Galaxy. I simply want you to understand the whole picture, Sink Ambassador.”

It hovered in space for a long time, complex standing waves shimmering across its surface. Then: “Very well. Jack Raoul — what do you know of dark matter?”