Disclaimer: I am not J K Rowling. I do not own Harry Potter.

Note: The following is a one-shot set in an alternate universe where Albus Dumbledore responds differently to the up till then canon events of Hallowe'en 1981 in Godric's Hollow.

'…you promised…'

His potions master's painful rebuke rang still in Albus Dumbledore's ears. Severus was hardly in any position of moral or ethical superiority to pass judgement on Albus, and Albus had quickly slapped him down, but the man had had a point, unfortunately, the headmaster of Hogwarts had had to privately acknowledge. Lily and James Potter were now dead, and he had put them in the position which had resulted in them winding up dead. He could have used his contacts overseas, if he had been inclined, to remove them from the country and make them disappear from the wizarding world altogether. Voldemort would never have found them. But they had stayed in the country – the uncharitable might say Albus had used them as bait – and now they were gone, as was Voldemort, however temporarily. Albus Dumbledore wasn't completely certain at this point, but from what information he had acquired he was reasonably certain that Voldemort had at least taken some sort of steps to try and ensure that any demise would be strictly temporary. There were a variety of ways he could have set something up which would have a reasonable chance of ensuring his return unless the mechanism selected could be identified and dismantled.

Albus Dumbledore was now on the horns of a highly painful dilemma. His initial thought had been to simply place Harry with the Dursley's, his aunt Petunia being his mother's only known living relative. Minerva had recollected that Severus Snape had lived in much the same neighbourhood as Lily and her sister Petunia when they had been growing up and demanded Albus summon him to give an account of what he knew of Lily's sister. According to Severus, rejection from the magical world had soured Petunia on all things magical, and James Potter and his friends had further made themselves obnoxious to her. At best Harry could expect to be treated with indifference if placed with her by the sound of it. Albus had placed protections on Harry, but the clock was ticking, and he needed to get him a home, ideally with blood kin, before the night was out.

Sirius Black, the godfather might have been an option if there had been time to vet him, but he had been due to be the Potters' secret keeper, as far as Albus knew, and someone had clearly betrayed the Potters to Voldemort. Besides which, Sirius had disappeared.

Albus Dumbledore felt very tired. This whole war against Voldemort had called upon him to make sacrifices of friends and allies – and made demands upon his judgement – which had sorely tested him. He had made mistakes. He had hoped that Gellert Grindelwald would be the last dark lord that would ever have to be opposed in his lifetime. No such luck.

Given the night, there was one option that Albus could try. There was so much to do that he would have to borrow a ministry time-turner to set this up, however – and it was old magic which would come at a substantial price.

Severus Snape had been summoned by Professor Dumbledore and was in the headmaster's office for the third time this night. The first time it had been in shock over Lily's death, the second time it had been because the headmaster had required information from him about Petunia Evans, now Petunia Dursley, and this third and final time, Dumbledore was dressing up, with Fawkes perched on his shoulder, to go out somewhere. There was a neat array of vials of silvery memories lined up on the headmaster's desk.

"I'm going off on an errand, Severus." the headmaster had said. "I don't know if I will be coming back. I require you to hold the fort here, so to speak, until I do, or Minerva returns. I am holding you here to the promise you once gave me that you would do anything. If I do not return, the memories are for either Minerva or someone she returns with. Obviously if I do not come back, I will be unable to personally protect you from investigations into Death Eaters. I've left written directions and memories with appropriate authorities as far as I can, but I am uncertain how far they will keep you safe from the prosecutions which will follow. It may be that a cell in Azkaban awaits, though I think the kiss will be ruled out, and I have hopes that a life-sentence will be averted." He had paused to give him a brief look of pity or of sympathy. "I'm sorry Severus."

And then he had gone, leaving Severus to await whatever doom came.

Shortly after midnight Minerva McGonagall had been sent a patronus messenger by the headmaster requiring her to attend a particular chamber in the depths of the Ministry of Magic, to bring Harry with her, and to wait with Harry, until either the headmaster or a messenger from him arrived. The patronus had stated that the headmaster had made arrangements with the ministry for her to be allowed access.

So here she was, in the chill air of the room where in old days the ministry had executed criminals by pushing them through a mysterious veil which was a one-way trip out of this life.

It gave her the creeps, and she had no idea why Albus wanted her waiting here with a child to meet him.

There was an unspeakable present – one of the workers of the department of mysteries – who had been here since before she arrived, and who simply stood there, unmoving and unspeaking, watching. Minerva had tried to question the man, thinking at first he must be Albus' messenger, but he had turned his eyes on her and said, in an emotionless voice 'Wait.' and that had been it.

So she waited.

Lily Potter had dreamt of a silvery place of shining white light, and such peace and tranquillity, where she had been with James. They had been sad for a little while, but gradually that had faded, and there had been so many other friends and relatives they had known there.

And then, she had had a sense of something going wrong, and there had been a dark tear and Albus Dumbledore had appeared. He had been struggling towards her, his wand clutched in one hand pointing forwards, as if fighting a current, whilst the phoenix, Fawkes, circled and wheeled over his head. And somehow, by means that Lily did not understand, Albus Dumbledore, her former mentor, was clutching her cold, unmoving, body in his arms, as she stood and watched him.

"Please, Lily." he had shouted over the roaring dissonance his intrusion had brought to this place. "Harry needs you. You have to go back."

Lily didn't understand – she was reasonably certain that this was a place it was completely impossible to go back from.

Dumbledore was struggling to remain here. He was not supposed to belong.

And Fawkes trilled sadly, and in the phoenix's song Lily understood. Dumbledore was offering to swap places with her, the phoenix could make this possible, and Dumbledore's wand could let her return.

Lily turned to look at James, and he whispered in her ear, and smiled sadly at her:

"We both know you have to go."

And he was right. Her son was waiting for her. He needed his mother.

And there had come the roaring torrent of phoenix fire, engulfing her and turning her body to ashes, as Dumbledore staggered and reeled, and then a moment where she rose from the fire, and they were both alive in that place, as the phoenix fire died away, and before it was completely gone Dumbledore had pressed his wand into her hand.

Lily had barely had time to blow a kiss of farewell to James before the last embers died, and Dumbledore changed and belonged and suddenly she was being tossed towards the black tear through which Dumbledore had entered, as she clutched desperately at the wand Dumbledore had given her, the only thing keeping her alive in this place.

Minerva was roused from a near-doze by a roaring cascade of silver fire which suddenly burst forth from the veil, and in the midst of it, as a mournfully calling phoenix shot out overhead, a woman was tossed out of the veil to spin through the air and then thump, with a painful gasp, to the floor almost at Minerva's feet. She was red haired, and wearing nothing, but clutched a wand that looked suspiciously like Albus Dumbledore's in her hand.

The fire died and the phoenix was gone and the woman winced and looked up, and Minerva looked down into what she'd swear were the green eyes of Lily Potter.

"So passes Albus Percival Wulfric Brian Dumbledore." the unspeakable said, as Minerva and the woman stared at one another.

Minerva had conjured a temporary set of robes for the woman, who seemed exhausted, and took her back to Hogwarts. Harry seemed to recognise the woman, and had tugged at her hair. Minerva couldn't be certain if this was actually Lily Potter or some creature or other being that wore her form. Nothing was ever known to have come out of the veil ever before.

She left the woman in the infirmary, after Poppy had given her a sleeping draught, with Harry in a cot next to her. The woman certainly seemed to reassure Harry as if she were his mother.

Then Minerva went to the headmaster's office, hoping Albus might have left her some sort of explanation. She found Severus in occupation guarding an array of vials containing memories, and a sealed enveloped addressed to her.

Severus wanted to know what was going on, but to be frank Minerva wasn't too sure, and she ignored him whilst she opened the envelope and scanned the letter contained.

Minerva,

If you are reading this, assume that I am gone. You were right, of course, that I can't leave Harry with the Dursleys, and Severus is correct to some extent (I leave it to your discretion whether to inform him I said this or not) that I am at least partially to blame for not protecting the Potters better than I did. Harry needs protection, but with Sirius missing and suspicions which I have (which might be unfounded, but I cannot afford to take the risk) that he may have betrayed the Potters there are very few options I see for providing the best protection.

This latest war has left me very tired. It is over, for now, bar the punishments of some of the guilty, and the rewarding of some of the just, and there is a breathing space now for others to spread their wings and take charge before the next crisis is upon us. I believe that – given the dearth of what I consider to be viable alternatives – Harry requires his mother, and so I am setting out for what will have been, if you are reading this, one last great adventure into the Department of Mysteries to try and exchange my own life for that of Lily Potter. With Fawkes on my shoulder and what I believe to be the Wand of Destiny (one of the Deathly Hallows) in my hand, I feel I have at least an even chance if I carry Lily's body through the veil that she may be able to return, to live once more. I do not know if it will work. I leave Hogwarts in your capable hands, for now, although if I am successful, I would ask you try to get Lily onto the staff, if she wishes it. All the memories on my desk are for Lily, if she returns, containing information I consider critical for her to know. If I am unsuccessful and she does not return, I would ask you to consider destroying them, unviewed, as some of them contain information I am sworn to at least one person to keep in confidence.

Please look after Harry as your own, if my errand fails.

Yours,

Albus Percival Wulfric Brian Dumbledore.

PS

I had borrowed James' heirloom invisibility cloak. I am leaving it in your office to pass on where and when you consider appropriate.

"Albus is gone." Minerva said, having read the letter through twice, and looking now at last at Snape. "He went off on one last crazy mission of his own, to try and tidy up some loose ends."

Snape went very pale.

"What was it?"

"I don't know I can tell you right now, Severus." Minerva said. "I need you to do one thing before you can retire to bed. I need you to stop by the infirmary and take a look through the mind of a patient I brought back with me and report back to me on what you find." She frowned. "Fortunately it's the weekend, so no lessons tomorrow and we can all catch up with our sleep."

She looked at the various paperwork spread across the headmaster's desk, and which was now about to be her exclusive responsibility. The governors would meet at some point to confirm a new head, and if necessary a replacement deputy, but for now the school was in Minerva's care.

She was awoken from a dream about broomstick budgets, by Snape's return. He looked wild-eyed and dumbfounded.

"What's going on?" he demanded. "That's Lily Potter in our infirmary. She was dead. I saw her body. Moody and the aurors retrieved it from Godric's Hollow."

"Trick or treat, Severus." Minerva mumbled. "Courtesy of You-Know-Who and our late esteemed headmaster. Now thank-you and go and get some rest."

She made arrangements to try and minimise any further disturbances, and then tried to make herself comfortable again, resting her head in her arms on the pile of papers. She figured she had a better chance of not being disturbed here, as acting headmistress, than anywhere else in the castle.

The goblins had been quite irate about the situation, and legal representatives had inevitably become involved. In the end because it had been Hallowe'en, and because the wills had never actually been formally read, it was decided that Lily Potter, nee Lily Evans, had legally been in a state of being 'almost dead' for however many hours it had been between Voldemort's attack in Godric's Hollow and her emerging from the veil in the Department of Mysteries. The last of the red tape was still being dealt with, but James' last will and testament was being activated as if he had died but not Lily, and Lily's had been left unactivated. The fact that Voldemort had killed James before Lily had helped considerably; it would have been a legal nightmare if their positions had been reversed.

After a stay of several days in the Hogwarts infirmary, during which there was a steady stream of owl correspondence with Gringotts, Lily was at last released and went to the acting headmistress' office to view the memories which the late headmaster had left her.

Lily emerged shaken, and went directly to confront the potions master. She now knew exactly who had set Voldemort on her trail, but also the desperate man who had pleaded with Dumbledore to save the Potters – all three of them – and who had been utterly devastated to learn that Dumbledore's attempts to keep them hidden and safe had failed. She exacted her own vow from him to assist her in protecting her son, whatever the cost may be to him.

And then she had James' funeral to deal with, of course, and the nagging suspicions after that to worry about that Dumbledore had had that Tom Marvolo Riddle, also known as Lord Voldemort, might have taken steps to achieve his own return from death, some day...

Author Notes:

Hallowe'en is, in European mythology, a time when the line between the living and the dead is supposedly blurred, which is partially where the idea for this story came from.

Dumbledore doesn't try to involve the Potter invisibility cloak in proceedings, since he's trying to give this the best shot he can at working, and he figures that trying to cheat the system needs to be kept to a minimum. He doesn't have any rightful claim to the cloak (unlike the wand) as far as the Deathly Hallows go, so he leaves it at Hogwarts. Likewise, he keeps his attempted trade of a life for a life at one-for-one, and picks Harry's mother on the basis that she's probably the parent it would be most beneficial to Harry to have around again, if this works.

It trails off a bit at the end, as I wasn't sure where things would go beyond the immediate and obvious events. I have no intentions at present of developing this as anything more than a one-shot.