Let's recap the last ten minutes, shall we?

I decoded the Keeper's infokey only to suffer a massive, shattering blow to everything that I've held to be true these last few months. This was followed by a momentary and entirely understandable lapse into fear and disorientation, which would presumably have remained the case had I not been interrupted by the sudden, unexplained arrival of a massive Richard Roundtree impersonator with a very strange watch who then vanished.

Yes, that's it.

Well, now… That actually happened…

I give myself a quick once-over with the sonic and no, I'm not under the influence of any outside force or narcotic substance. And I'm aware enough to have given myself a quick once-over with the sonic, so that rules out some kind of psychotic break.

And then he reappears. Not at the point from which he vanished, down on the floor by the downstairs doorway.

"Hello again."

"You're the Doctor, man, that right?"

"Oh, no formalities, straight down to business, right, fine, that's nice, yes I am."

"Ain't got no time to be polite," he says. Comes running up the stairs and grabs my hand to shake it. "But if it means that much to you, Hamunaptra Jones, sir, pleasure to make your acquaintance."

"Hamunaptra?"

"Call me Mun, it's quicker. Took me a dog's age to find you, brother, you and me gotta talk about something-" 'Quicker' would indeed seem to be the order of the day. For all his enviable calm, Mr Mun Jones is speaking incredibly quickly. My head spins, and it was already thumping, and I don't really have the energy for this, so I shut my eyes and raise a hand to make him stop. Eventually, he notices. "What, man?"

I can formulate no question more complicated than, "Who are you?"

"Ain't no time for that," he says. Face set firm, folding his arms across a chest so big it's a wonder they can stretch.

"I really should insist, you know."

Shaking his great huge afro, "Ain't no time." I wonder would there be time if I was asking him how he gets his hair to do that. I told you already, I'm just not up to this right now, and neither am I in the mood. I don't mean to snap at him, but I do.

"Listen, tell me who the hell you are or get off my Tardis."

He sighs, like I'm really putting him awfully far out of his way, and rattles this next off in one breath. "I'm called Hamunaptra Jones and I'm the best undercover man the Justice Department has, or I used to be anyhow, and I just landed in by accident on a meeting you really need to let me talk at you about only you're being too damn British, man, to have that happen, now will you sit your ass down and be satisfied?"

I sit down. Not because he told me to, I just needed to. I am, however, most definitely not satisfied.

I open my mouth to tell him so, and his wrist beeps.

"Damn, man, next time I come back here you gotta stop talking so much."

Beep. "Me?"

"Listen to me, don't move, I only got-" And on the third beep, as before, he disappears. Vanishes out of the world like he was never there to begin with. Which I'm still willing to consider as an option. I could well have lost my mind. Very likely I should go and get the Ponds and have them tell me that no, there is no trace whatever of an enormous gentleman in a beaded waistcoat.

But then again, he told me not to move. Trying to explain something when he disappeared. For all I know I'm sitting on a mind, though that seems unlikely. I imagine a mine would be much less comfortable than my chair is.

Nonetheless, I imagine he was telling me not to move for a reason. He seems to mean me no direct harm at least.

Which he wouldn't, if he was a figment of my imagination.

Actually, he'd better be a figment of his imagination. I was in no mood to receive visitors today and should this man, this Mun, actually be a real actual physical person then he is very much an intruder here in my home at a very delicate moment in my life. How dare he make me think I'm going mad, if I'm not. Which I might be.

Oh, he's back. Appears on the other set of stairs this time, but immediately rushes over to me. Opens his mouth to speak, but I raise up one finger. He shuts his mouth, most accommodating, but looks very much as though it annoys him to do so.

"First things first, will be all be blown to pieces if I stand up?"

"No, man."

So I stand up and shove him in the chest. It doesn't do much more than mildly sway him. I didn't expect it to. But I very definitely felt flesh and beaded waistcoat under my hand, so I know he's real, at least. "Then why did you tell me not to move?"

"Oh, no, not you, brother, not move your Tardis. Otherwise I wouldn't have been able to find you again. Now listen-"

"No, you listen, Mr Jones-"

"Ain't no-"

"It's a time machine, my friend, you cannot use that argument here. Now I was rather in the middle of something when you decided to just appear and I'd like it very much if you'd go away for a while." That sounded rather more threat-like in my head. I'm just a tiny bit ashamed of how it eventually came out. I'm not embarrassed, though; he's not even listening to me. He's checking his watch. No. No, he's turning his wrist over, looking into that mangled mass of digitised flesh. The LED numbers are shifting, too fast to keep reading. One at a time, however, they settle and stop. He's got seven out of thirteen numbers on.

"That's the third time you've done that," I say. "I mean, since you came back. Are we still on a timer?"

"Like you got no idea, man. Just me, though, not we. I'm gonna flash out again real soon, but I'll be back the minute after. Don't go anyplace, man, don't move this machine, I only got one set of co-ordinates for you and you need to know what I gotta tell you, you dig?"

Sometimes. With a shovel. Usually when there are things that need to be dug up. Occasionally because there is something which needs to be buried. I tell him that, but Mun ain't got no time to listen to that kind of thing. He's on the other side of my console, with my monitor and my keyboard and he's using them.

"Oh, certainly," I say. "Go ahead, knock yourself out, do whatever you need to do."

"Well, if you don't mind, I don't gotta ask now, do I?" But it's the principle of the thing, I want to tell him. But he'll only tell me there ain't no time for principles of things. "I'm gonna leave you with something oughta explain things for you. Time you get through it, probably I'll be back."

His wrist beeps again and goes right through my pulsing brain.

"What is making that noise?"

"Million dollar question, Doctor. I get time someday, maybe I'll ask you." And it beeps again. "See you on the other side, man." And on the third beep, one more time, he's gone.