Disclaimer: I do not own any the Mortal Instruments and Infernal Devices series and so in turn the characters are not mine.

"We have both told you all of those things already. I am exactly who I say I am. I am a Shadowhunter. Where have I come from? USA. The problem is not who I am or where I have come from, it's when I've come from that is the issue," said Jace. The game of covering up the impossible was becoming too tiresome.

"What do you mean to say by that?" Magnus whispered slowly. As Jace looked at him he could almost see the cogs turning in the warlock's mind. He knew. Somehow Magnus already knew.

"You have your answers but you refuse to believe them," said Jace.

The clock carried on ticking on the mantelpiece and birds (mostly pigeons) cried out for attention outside. Everything was the same as it was before Jace had spoken everything except Magnus who took a deep breath and stared at the ticking clock.

"Quarter past eleven," he murmured to himself.

"Are you even listening to me?" Jace demanded.

"Oh, I heard you. You are right, I must admit. I have been terribly and wilfully ignorant." He giggled to himself like a mad man. "What sort of Warlock am I? Who is this Magnus Bane who would deny what is, essentially, possible."

He turned to Jace with a wide smile. "Thank you. I don't often say that to people, but thank you." He raised a hand and Jace fell to the floor. Gently Magnus draped his limp body on an armchair.

Magnus touched the young man's face. "Sorry about that. Well, I'm not completely sorry. I need space and time to think."

He walked back to the library. When he had sat there earlier he hadn't even considered the idea that time travel could be involved. 'A different Magnus Bane' Alexander had said. It was all too clear to him now. It was the only thing that made sense and it was possible.

They must be from the future. I've never met them before today and I would know those eyes. And the way they dressed, I've never seen clothes quite like that before. How could I have been so stupid? Still, this is no time to linger on the past. Preparations must be made for the future.

He sat down at a desk and began to write:

Dear Myself,

This letter is very difficult for me to write. I have been a fool and ignored the facts that have been staring at me for the last few days.

I write this letter so you can be informed when the time comes. There is a young man here called Alexander Lightwood. I have never seen him before in my life however it appears that I most definitely will in the future.

My hope is that this name will mean something to you because he and you are my future.

When I have talked to him I have seen love in his eyes. And anger, if I am to be truthful (and if I cannot be truthful to myself then I am lost). But I believe this love is not meant for me, but is hopefully earned by you (whilst the anger was aimed at me alone).

He will end up in your past. (If you hadn't worked that out by this point in my letter, then my intelligence has degraded rapidly in my old age which would be a most unfortunate occurrence so I will not linger for too long on that possibility).

The important thing you need to know is that you must not interfere with the event that brings him here. I will deal with this side of things and you must sit and wait for him to return. I'm sure that will be a difficult task but if there will exist a love between him and I in the future then you have no reason to doubt that I will protect my future assets.

Events like this can shape a person. Alexander being here will change him which is why you must let it be. It is his fate, if you will allow me to use that phrase. You will not remember meeting him before, again I shall deal with that aspect. But whilst I will remove the memories I cannot promise that it will not change something in me to have met that young man. Which is another reason why we must let this event occur because you are the result of everything that has happened to me including this event no matter how suppressed it may be in my mind.

I promise to take care of him.

Yours sincerely,

Magnus Bane

(I need not tell you how magnificent I am, of course.)

He slotted the letter in to a golden envelope and left the house. There was only one person he could trust with this letter. Tessa, beautiful, enchanting, trustworthy Tessa.

Tessa took the envelope from his hand as gently as if it were made of china.

"How will I know when to give it you?" she asked.

"The day I tell you that I have fallen in love with a Lightwood," Magnus replied, not meeting her eyes.

"So it's true. Will and Jem told me about what happened earlier in the week. Only your relationship with this gentleman is all backwards."

"You have it one, Miss Gray."

"And you won't remember giving me this letter or meeting him?"

"No. I have decided against it. It would make things too complicated. Besides," he grinned. "I don't want to spoil the moment when he first meets me. When that time comes I will be ready for him in a way that I am not now."

In the present:

She had waited until Christmas before she gave him the letter. She didn't even give him a chance to discuss it with her. She did not want to be put on the spot and forced to recite what he had, in the past, insisted on forgetting.

Casually she had walked in to a restaurant where they were having a meal and she had just left it there, on the table. When she arrivedi t was clear they had been arguing and the look Alexander Lightwood gave her in that moment when Magnus recognised her had made her worry that she may have aggravated things just by appearing. That was why she did not hang around after she had discharged her duty.

Magnus did not open the letter. His day had been fractious. Alec had been in a bad mood and they had parted on a sour note because of it. That was why when he got home he threw the envelope in a corner and soon forgot about it. If Tessa had wanted something surely she would have just spoken to him? She knows where I live if she needs me. I have no time to play covert games. He thought this to himself in a fit of annoyance, annoyance that had been inspired by Alec.

All those years Tessa Gray had carried his letter and Magnus had not even bothered to open it at the right time. But now with his lover lost in time that gold envelope was catching his eye. Could it be? Could it be something to do with all of this?