I try leaving them. They might as well enjoy themselves. God alone knows where River is; I owe them that much at least. There are things I can be getting on with in the meantime and should I require their assistance at any time I can shout very, very loudly. While Dublin is in fresh blue bloom, the Ponds can have a good time.

But they do so love to follow me around. I have honestly checked my boot heels for magnets on occasion, you know. Some kind of companion-attractant force generator. Something. Must be something going on.

Note to self: companion-attractant force generator is a really good idea. Stop them wandering off.

Anyway, they're not willing to let go of the adventure just yet, which I suppose should make me happy. Yay. See? There, I tried. We're going to see one Professor McDonagh, here at the College, who has his offices beyond the library. An old friend of mine. And it would have been nice to be able to speak freely with him about certain things, but he won't if there are others. Nevertheless, yay.

Here's to companion spirit.

Yeah, I'm not capitalizing that anymore.

Still nice to see him, though. McDonagh's office door doesn't open all the way anymore. There are books stacked behind that. How do I know that, if the door won't open and I can't see round it? There are books stacked everywhere, it's an educated guess. And papers, and tablets. Stone tablets. Great hunks of runic history everywhere. "Hello?" I call, slipping through the little gap there is. "Something's going to fall on you someday, you k-" I'm cut off, but the sound of the landslide behind me. Pushing too hard against the door it would seem. "Oh, God, don't be dead."

"I'm over here, y'eejit," he says. He's in the other corner. Where I could have seen him if I was looking. Finishes, "But you're tidying that up before you go." Professor McDonagh stands at little over five feet, a hooked, withered old man with a tiny white beard and tinier gold-rimmed glasses. He's stern and straight-faced when he says that, but as I watch he breaks into a grin. "How did I know you'd show up?"

"Oh, because there were great big alien trees springing up through the floor, I suppose."

It should be awkward to hug him. He gets me around the chest and it's not awkward at all. Great old gent, McDonagh.

"Wait," Pond says, "Alien trees?"

"Now where was the last place you saw a blue tree, missus?" McDonagh lets go of me to take Pond by the hand. "And who would you be?"

I make brief introductions, and make very clear that those two are married, because I know what he's like. McDonagh invites us all to be seated, which mostly involves perching on desk edges or those precarious stacks. I want a photograph of Amy on top of a pile of proto-Celtic dictionaries. I want to tag it 'The Pixie of the Library' and sneak it onto her Facebook page. But that's a horrible, silly little whim and I shake it off, and I absolutely don't think about it the entire time she's sitting there.

Rory is shaking his head, slightly open-mouthed. Either he's thinking the same thing I am about getting a photo of Pond, which is unlikely, or he disbelieves something. I look at him, nod a prompt. Best get this out of the way before we discuss anything actually serious, "Yes?"

"You've got a professor in every port."

McDonagh cuts in, all smiling and sly, "Ah, but he only takes the best with him. Never would let me into that box of his."

"Don't start that again," I tell him and, satisfied that Rory's quite done, get down to business. "So, alien trees aside or kept for later, I do need to ask you something."

"Anything you want."

"Where are we on contacting the Tir?" He stops. Plain as subtitles, his expression says, 'Anything but that.' "It's important, McDonagh, they've got a friend of ours. A very important friend." Not in and of herself, you understand, but very important in that I followed her instead of River and I have to make good on something, have to do something right. And McDonagh's been working on this for more years than either of us cares to count, so it's difficult to understand just why he chooses now to turn so standoffish.

"Look out the window, Doctor. They're contacting us."

A couple of inches more and the white-leaved branch is going to be coming through the window.

"That's them?"
"That's exactly them. That's Tirinnanoc in the Trinity courtyard. Other places, too."

"There are more of these gardens?"

"One at the Ha'penny Bridge, one at the end of Grafton Street. Molly Malone's got more shelter than she ever had." His eyes shift and refocus, over my shoulder. That sly, one-sided smile again. "Ah, bless their cotton socks, they're gone."

"Completely," Rory agrees. Pond nods along.

McDonagh looks at me. "Do you want to explain to them?"

"No, you go ahead. You have that Irish lilt in your voice, everything sounds like a bedtime story; it's wonderful." Also, there are parts of it I couldn't really tell, due to my having absolutely no clue. But it just would not do to say such things in front of companions. Never hear the end of it.

McDonagh settles himself, breathes deep and begins. "Once upon a time, way, way back, when Dublin was a couple of huts next to a river, there was a mystic settlement in roughly the same place. Tirinnanoc, the home of the Tir. A beautiful people who never aged or died, who lived for pleasure and wanted for nothing."

"Oh, Professor, don't," Pond moans, eyes closed and jealously dreaming.

"Well, you see, the other humans felt like you do. Got envious and decided to drive the Tir out. So the Tir went away, and they took Tirinnanoc with them. They disappeared, and faded amongst the humans into simple myth, a fairy story."

"So where did they go?" Rory asks. I told you he'd make it sound like a fairytale; they're hanging on his every word, like children who don't want to go to sleep yet.

"Nowhere," McDonagh grins.

"But you said-"

"They're still here."

"Oh, you old tease," I snap at him, and turn in my chair to explain to Rory, "They moved out of time, not out of the area. Made themselves a little pocket of the universe in the same spot as they were before, just out of the way of the humans."

"Like an alternate universe," he tries.

"No, God, heavens Rory, no, don't even say that, let's not talk about alternate universes, it's not like that at all, don't think about those, don't mention those, just-"

"Doctor?"

"…No."

Now, for you at home, I'll make it simple. Dublin is Tirinnanoc, and Tirinnanoc is Dublin. It's just that the two never meet. Like parallel lines. Except, apparently, out in that courtyard and at two other places in town, they've met. Crossed over. A crowd of Spanish tourists are having their photograph taken hanging from the lower boughs of an alien civilization that got here before the Romans did, and probably before Ireland broke off from that little corner around England and Wales.

All of this just as Jessica is kidnapped by one of the Tir.

Coincidences are great, aren't they? I like coincidences. Well, some of them. Ones like this, that make sense and have no missing links, those are great.

"Just the gardens?" I ask McDonagh, "No sign of the Tir themselves?"

He should say yes. That would mean they were going back and forth. That would mean crossing back and forth had gotten a lot easier since the last time it was attempted.

"No."

Can't have it all, I suppose.

"Well, there've been… reports."

"Reports? What reports? I'll take a report, we could look into a report, couldn't we, Ponds? What kind of report? Damn it, man, report."

"The Morrigan. Reports of The Morrigan appearing at the gardens, on horseback, in full leather armour."

Pond asks what a Morrigan is. Rory, in that blank-faced way he has when he's referencing the life he never had anymore, fills automatically, "The heathen war goddess of the Celt barbarians."

McDonagh shifts. Barely perceptible, a slight raising of the brow, a tightening of the usual benevolent smile. I lean forward and pat his arm. "Ignore him, he was a centurion for a while."

McDonagh shifts again. Funny feeling I might have made things worse than they already were. "Was he now?" is all McDonagh says, and settles back in his chair, cautiously eyeing Rory. "But yes, that's who they're saying it is. Then again we've had a plague of pagans and hippies descend upon us since they grew, so God only knows what they think they've seen."

"Oh, don't be such a cynic. I think the Morrigan's a wonderful idea. I think we should go and look for the Morrigan. I think the Ponds should start looking for the Morrigan out in the hallway until I join them." Not, you understand, the subtlest hint I've ever dropped, and yet it still takes them a good five seconds of silence before they pick it up.

My only thought between implying that they should leave and them leaving occurs when Rory helps Pond down from those books. 'There goes the photo op,' is my thought. Then the door closes behind them, and a former cairn stone slumps emphatically against the jamb.

"What's the matter?" I say to McDonagh.

He gets up and goes to the window rather than answering. I stand near him, but give him his space. I know, and know well, the look in his eyes as he gazes on that garden, on the old world bursting into the new. A place lost. He raises his hand, as if to set it against the glass, then changes his mind about even that much contact.

"You're not to be blamed, you'd no way of knowing. But I gave up trying to talk to the Tir a long lot of years ago."

"What? Why? I thought it was all you'd ever wanted since-"

"And it was. But think about it, Doctor, just step back and think about it for a minute. What good was it ever going to do for me?"

I want not to understand that. I want to tell him off for giving up, for being so defeatist. But the truth is I know the reasons behind it and I can't blame him. It becomes very, very difficult indeed to swallow the lump in my throat. More difficult still to put a hand on his shoulder and ask, "But can you still help me?"

It's clear, everything about him makes it clear, that he doesn't want to. This is a part of his long life he has walked away from and does not want to touch. Then again, it is currently tapping at his office window in every little breeze. After a moment's consideration, he places his hand over mine and nods. "Give me an hour or two. I still have the research, I'll dig it out for you. I'm afraid that's the best I can do."

Less than I'd hoped and more than I could ask of him. I thank him and go back to the Ponds.