"ALBUS PERCIVAL WULFRIC BRIAN DUMBLEDORE!" shouted an angry James Potter at the man in the round office at the Hogwarts School of Witchcraft and Wizardry. He reached out with his hands to throttle the headmaster's throat and shake him, but the headmaster only felt an unpleasant chill. James was a ghost, you see.
Realizing that the most he could do was make him uncomfortable, James zoomed back and forth through Albus's chest several times and then stopped to confront him again.
"What were you thinking ABANDONING MY SON on the doorstep of Petunia Dursley?" asked the incensed ghost.
"Ah, James, it's good to see you, too" responded Albus without answering the question, as was his habit. "I'd offer you a sherbet lemon, but alas I can see that in your current state it would be difficult for you to partake of this delightful pleasure."
"Answer the question Albus!" demanded James, arms akimbo.
"Well, James, I really had Harry's best interests at heart and was thinking of his safety. You see, a killing curse reflected off Harry and destroyed Voldemort so I had to protect him from Death Eaters who might want to take revenge on the lad" disclosed Albus.
"What's that got to do with the price of tea in China, Albus? What made you think he would be safe at the Dursleys?" anger still flashing in James's eyes.
"I set up blood wards on the Dursley property because that's where Lily's only kin live and I needed someone who shared her bloodline" revealed Albus.
"And why did you need her bloodline, pray tell?" asked James in a rather icy tone, folding his arms across his chest.
"When I examined the magical residues at your cottage in Godric's Hollow it was clear that after Voldemort had killed you and Lily, he then aimed a final killing curse at Harry which reflected off the lad's forehead back onto himself. The only way I could countenance that such a scenario might have occurred is if Lily had quickly cast a protection charm that used her own death as a blood sacrifice to somehow create a previously unheard-of level of protection for him" Albus propounded.
"So what you're telling me is that based upon that faulty ASSUMPTION, that mere GUESS, that WISHFUL THINKING based upon INCOMPLETE KNOWLEDGE, you disregarded our express instructions to the contrary and went out and put dodgy obsolete wards on my sister-in-law's property without her permission and then casually dropped off my son on her doorstep like a mere PARCEL sent through the POST!" exclaimed James with as much heat as a ghost can muster. James was leaning forward over the desk with his hands flat on the desk blotter. He was in Albus's face enough that if he'd had spittle it would have hit the man seated behind the desk when he pronounced his pees.
Albus leaned back as much as he could in his chair and said meekly "Sorry, James, I did what I thought would give him the most protection from dangers that still lurk."
James stood straight and stated icily "Sorry won't cut it Albus, and neither will those wards. Lily and I were watching you from Beyond. You didn't even ring the doorbell or shout 'Special Delivery!' which is why I got permission to haunt you. And you'd better hope you don't give cause for Lily to be sent—she's not a very forgiving person, Albus."
James took a seat and continued "Your theory is wrong. Lily never cast any blood sacrifice protection charm. I doubt she even knows one; she's never mentioned it to me. In her haste to pick up the baby and run from the room she forgot her wand so she couldn't have cast anything. I noticed it and picked it up and managed to cast a diffindo curse with mine and a protego shield with hers as Voldemort was coming through the door, but he was able to bat my curse back at me and cast an avada kedavra at the same time. I tripped trying to dodge the A.K.—Harry had been playing on the rug with some stuffed animals—I'd stepped on the stuffed rat and down I went. I lasted only long enough for Lily to make it out of the room with Harry in her arms. She was with me in less than a minute and we crossed over together."
The ghost fingered the signet ring on his hand and then looked Albus in the eyes. "You forgot something very important when you considered the possibilities, Albus. You forgot that I inherited my invisibility cloak from Ignotus Peverell, the first Friend of Death. Lily's blood has no saving power. What saved Harry came from MY legacy. How does the Tale of the Three Brothers end Albus? I know you know!" he chided.
Albus quoted the last sentence verbatim "And then he greeted Death as an old friend, and went with him gladly, and, equals, they departed this life."
"Not quite enough, include the sentence before that, please" James urged.
Albus quoted "It was only when he had attained a great age that the youngest brother finally took off the Cloak of Invisibility and gave it to his son. And then he greeted Death as an old friend, and went with him gladly, and, equals, they departed this life."
"There, you see? Death granted Ignotus the favor of delaying his departure from life until after he had a son, Iago, to whom he'd passed on his legacy" stated James with excitement in his voice. "The cloak is only a token that represents the legacy in the tale; it's not the whole legacy. The most valuable part of the legacy is Ignotus's journals and his copy of the Peverell Grimoire."
"What are you telling me, James?" inquired Albus with all the intellectual curiosity the formidable man could focus.
"I'm saying that when Harry was born I performed a ritual on him from the Peverell Grimoire that 'hides him from Death' until he performs the same ceremony on someone else, presumably his own son or daughter. As long as the rite is performed on each generation, the Peverell legacy will continue and Death will have a Friend who does not fear him. The downside, of course, is that I had to sacrifice my own protection in order to give it to my son."
"I don't suppose you'd let me look at those writings?" asked Albus, eyes a-twinkle.
"I couldn't even if I wanted to, Albus" answered James. "They're charmed to look like mere squiggles to anyone who's not a Peverell heir. But that reminds me—the cloak is part of the legacy and I let you study it. That was a mistake on my part that I've regretted ever since. Lily and I should have had it to protect Harry. I never should have treated any part of the legacy so casually—My father scolded me about it as soon as I crossed over. I want your promise that you will never divulge what you learned from studying it, and that you'll return it as soon as possible—It's a sacred part of the Potter family legacy."
"I promise to do as you ask on my magic, James" answered Albus solemnly. His wand glowed blue to show his magic was binding him to his promise. Albus readily acquiesced because he knew James would not rest in peace until the matter was resolved and the last thing he wanted was to be haunted by the ghost of a prankster. It would be like having his own personal Peeves! (He shuddered at the thought.) Besides, there was an ancient magic from a Hebrew tradition called the Jubilee that could be invoked in certain years even from beyond the grave to force legacy holdings back into family hands.
"Thank you, Albus" responded James. "The next item on my agenda is getting Harry back from the Dursleys and into the hands of his godfather, Sirius Black."
"Sirius is in Azkaban and can't care for Harry even if I do retrieve him from the Dursleys" answered Albus.
James glowered fiercely at the wizened wizard "Don't you dare delay for one day in retrieving my son from those magic-hating gits. Lily and I were both explicit in our wills that Harry is NEVER to be placed with her sister. What part of 'UNDER ANY CIRCUMSTANCES' did you fail to understand Albus Dumbledore? You witnessed our wills. You have thirty days or the contractual magic of the documents will begin to force obedience to their terms. But I don't want you to wait anywhere near that long. Get on the floo right now and send Hagrid to retrieve my son from those bloody bigots." (Unfortunately, the magic associated with wills wouldn't be very effective in this case. It would cause a long-term blight on Albus's reputation such that people would tell horrible tales about what a bloody git he was for leaving Harry with the Dursleys, but since he did it with good intention and without profit to himself, the punishment wouldn't be severe enough that he would be forced to relent.)
Having been made aware that the blood wards wouldn't be anything special, Albus obeyed the ghost without further argument. Hagrid was happy to respond immediately. It would take several hours to fly between Scotland and Surrey and back on Sirius's motorbike, but Harry would be in the castle by morning. Albus took a moment to floo Minerva McGonagall and let her know of the change in plans for Harry. She was greatly relieved—she had expressed her strong disapproval of the initial placement. She asked to care for the child temporarily until he could be turned over to his godfather despite her heavy workload. She agreed to share that duty with Hagrid and Poppy Pomfrey.
When Albus returned to his desk, James said "Thank you, but you're job's not done yet. My best friend's suffering in Azkaban and he's an innocent man. Let's get the wheels of justice turning on his behalf. Sirius wasn't the secret keeper, he was the decoy. Peter was the secret keeper; he's the spy; he's the betrayer; and he's the one who framed Sirius."
Obediently, Albus took out a parchment with the official Wizengamot letterhead and wrote a Writ of Habeas Corpus directing the DMLE to produce Sirius Black for trial at the next Wizengamot session, and to schedule the trial accordingly. He flooed the DMLE and served the Writ on the duty clerk.
Hoping that Peter Pettigrew was not hiding in an unplottable location, Albus cast Peter Pettigrew quod directionis and found that he was somewhere south-southwest of Hogwarts. James let Albus know that Peter was an unregistered animagus and was probably hiding in his rat form. Albus wrote an arrest warrant for Peter Pettigrew and served it on the duty clerk at the DMLE, and let them know to be looking for a rat animagus currently somewhere unwarded SSW of Hogwarts. The Aurors were able to triangulate and determine that he was WSW of London. They were able to home in quickly and capture him in a field in rural Devonshire within the hour. Since they had to trample some standing stubble to capture him, the Muggle-Worthy Excuse Committee was called in to create a crop circle pattern to disguise the disarray.
After Albus ordered the arrest of Peter Pettigrew, James thanked him and bid him good night. James then hurried to Azkaban to let Sirius know that he'd soon be transferred to a holding cell at the Ministry while awaiting trial. James kept Sirius company until the trial, telling him everything he wanted Sirius to teach Harry about his family and his legacies. Since Sirius didn't have good memories of his own parents, James tried to recall all the good things his mother and father had done, especially those he most valued after they were gone—how they acted that showed they loved, cared for, and respected him, and the good advice they gave him that he wanted passed on to Harry. Fortunately, Sirius did have good memories of the times he spent visiting and living with James and his parents.
He told Sirius where Harry should find the Potter, Gryffindor and Peverell journals, grimoires and ancient texts. Where to look for his broom and his school trunk wherein he kept his copy of the Marauder map and the Marauder journal. Where Lily kept her personal Potions journal and Charms grimoire. Where the family photographs and portraits were. He and Lily didn't have finished portraits yet, but they had extracted personality essences and he told Sirius where those were stored along with photographs that they had selected for an artist to use to create their portraits.
He told him where the Potter properties were and what secrets they held and who the head house-elves were. Who the Potter solicitor was and what cases they were working on at the time of his death. Who the proxy was for the Gryffindor seat in the Wizengamot and the Hogwarts Board of Governors. He also contacted the Wizengamot proxy and made sure that Sirius would have an advocate at his trial. Sirius wanted to adopt Harry, and James welcomed the idea and told the solicitor to take care of that and even make it legal in the Muggle world so there would be no problem from the Dursleys or anyone else in the Evans family.
James had the honor of being a witness for the defense at Sirius's trial, testifying that Sirius was never the real secret keeper, only a decoy, and that the real secret keeper was Peter Pettigrew. The advocate had to search back 102 years to find a precedent that allowed for a ghost to testify in a criminal case.
After the trial, James had to return to Beyond. He didn't have permission to stay and visit with Harry or to help raise him. So he hugged Sirius (which felt like a bracingly cool shower to his live friend) and faded out of sight with a 'goodbye and good luck'.