Disclaimer: If I, and not the BBC, owned the Doctor and Donna, they would now be happily traveling the universe with their brood of ginger-haired Timebabies.

The Letter

"Shaun, love, can you get it for me? I don't think it will be long now."

"Of course, sweetheart" he responded to her barely-whispered request, giving her hand a squeeze and momentarily leaving their bedroom to retrieve what she had asked for.

After a few moments he returned and helped her to sit up a bit, propping up some pillows behind her. He sat down next to her and pressed an envelope into her hand.

She looked at it and turned it over, but there was no writing on the outside to indicate even that it was for her. She broke the seal, and took out the letter, which was a little yellowed and oddly rippled, as if it had been wet at some stage.

She felt Shaun's grip on her hand tighten a little. The handwriting looked strangely familiar, and for some reason she suddenly got an image of Post-its in her head that made her feel a little warm. She fanned herself momentarily with the letter before starting to read.

My dearest, dearest Donna

If you are reading this now, it means one of two things. Either Wilf managed to do as I asked and this has reached your hands because your time on earth is drawing to a close.

She closed her eyes for a moment, sighing. She was so tired. She missed her grandad.

Or else, being Donna, you have somehow managed to weedle this letter out of his hands before the appropriate time.

She couldn't help a little smile then.

If it is the latter case, STOP READING RIGHT NOW! I MEAN IT! TRUST ME, YOU DON'T WANT TO BE READNG THIS YET!

Again, with the strangeness. Who wrote letters like this?

The rest of the page was blank. So she turned to the next page. The familiar handwriting resumed.

Okay, if you're this far, I'm assuming you're in the former situation (and if not, I'm afraid you soon will be). Both of for which I am so, so sorry.

What you are about to read is not going to help with the above, and will in fact make it a lot worse, but I'm guessing (hoping, praying) that you're ready to take the next step, having lived a full and happy life. That is all I really ever wanted for you. Well, actually, that's not strictly true, what I really, really wanted was to have been able to share that full and happy life with you. But it was not to be and it was my greatest sadness until my dying day.

Even as she continued to wonder who had written this, images started to flit across her consciousness. Most of them didn't seem to make much sense.

Anyway, I'm sure you lived a wonderful, good life because you are brilliant and special. But Donna, you've never known how brilliant and special you really are. That you never knew was my fault, and I am very sorry. You deserved to know, to remember every amazing thing you ever did. But because of me and what I did to you, if you ever did, it would've literally destroyed you. I couldn't do that to you, I had already taken too much from you. Telling you now, now that you have lived your life and fulfilled so many dreams, was the only way I could be sure of not robbing you more than I already had.

Donna frowned, confused. But her curiosity was well and truly piqued, so she ploughed on.

Your grandad and I were great mates, and we would chat from time to time about the stars and adventures and good times. Mostly, though, we talked about you. I couldn't see you, it was too dangerous, so he kept me up to date on everything you were doing, how you were. He would show me pictures of your children and you having fun with your family, and I was happy to see that you were happy. Really, I was.

He also told me that sometimes you would get so sad, like there was something missing, but you couldn't work out what it was. My darling, I'm so terribly sorry about that and that you have had to wait so long, but please keep reading and I will do my best to give you back (all too late, I know) what you were missing all that time.

This guy is being just a bit too familiar with his prose, she thought. Why is that? Who is he to me?

I know it won't make up for all those years of sadness, and believe me, that is by far my biggest regret in my whole nine hundred year plus existence.

There was a sudden, sharp flash in Donna's mind as she saw a man, tall and thin, wearing some kind of suit. And with amazing hair.

Years ago, you and I knew each other. In fact, we were best friends. We travelled all around the universe together, saw the most amazing things, had the best of times.

We were a great team you and I, and together we did so many good things, things that helped so many. In fact, there are galaxies where they still sing songs about what we did, and of how brilliant you are.

The images were now much clearer and coming thick and fast. The Ood. Poison gas. Agatha Christie. The library. Pompeii. And flying fat.

Our last adventure was the most amazing of all, saved 27 worlds, the earth and even stopped the destruction of reality itself. It was you that did it. It's a bit complicated to explain, but you absorbed energy from me and took in my mind and saved everyone with your genius. I was so proud of you.

She saw his face now. Dazzling smile. Deep brown eyes. Intense expression. It was like she could almost feel him, fingers stroking her face, strong arms holding her, even as she fell…..Her eyes scrunched up as the pain in her head intensified.

But the Time Lord mind was too much for your human body.

It was killing you.

I couldn't bear the thought of a world without you in it, and so I locked away the memories and the energy away in the back of your mind to keep you safe. I was the one that made you forget. It was to save your life, I told myself, take your memories or watch you die in my arms. But it meant you could never know any of the spectacular things you did. And you could never know me. If you had seen me, you would have remembered and you would have died before you'd even had a chance to live. I couldn't do that to you. Sometimes I wonder if I did the right thing. I guess only you can say whether I did or not. I hope that maybe you might be able to understand why I did what I did. And maybe even forgive me.

Donna started shaking, and the tears fell. She remembered. Everything.

Believe me when I tell you that not being able to see you, be with you, talk with you – or to ever make love to you - I was dying a little more every day. As you know, I had travelled with other companions in the past, and whenever they left for one reason or another, I would eventually find another to travel with.

That all ended with you. You were the perfect partner for me. You were closer to me than anyone. And so when I had to leave you, I realised that I couldn't do it anymore. I couldn't travel with anyone ever again. You were it for me.

We were meant to be together. You found me once, and then, somehow, you found me again. That doesn't just 'happen'. There was something that destined us to meet. We'd only just found each other, but I knew even then that I was supposed to spend forever with you.

Remember how we both said we just wanted a mate? Well, I am absolutely certain that in time we would have become much more. You challenged me, complemented me, comforted me, you changed me for the better. Yes, you were the person I needed to stop me sometimes, but mostly you were just the person I NEEDED.

I'm guessing that you are remembering more and more now, and that means not much time is left.

So I want to tell you this, finally. I loved you – and I am sure that even when I am gone from this world, I will still love you – so, so much, with every part of my being. You once told me you would be with me forever, and can tell you that I wanted that more than I have wanted anything, ever. I'm so sorry our time together was so short, but I just needed you to know that you are brilliant and a genius and the most important woman in the entire universe (particularly to me).

And one day, if I am lucky, I will see you again.

My eternal love

The Doctor

The tears that had started running down Donna's face half way through the letter become a torrent when she read his name. Shaun was unable to stop either them or her hiccupping sobs.

The letter fluttered out of her hands on to the bed as she collapsed to the pillow, her head growing hotter and hotter until all she could see and feel was a white hot sear that obliterated everything.

She never heard Shaun's cry of agony or felt his arms cradle her dying form in his arms.

But she did see the Doctor, leaning on the door of the TARDIS, waiting for her, his smile wider than she had ever seen.

And so she ran to him.