Harry felt like he was being both torn apart and burned alive.
The journey through Merlin's Ring could not have lasted more than a few seconds, but it felt like an eternity before he and Luna finally stumbled out the other end of the vortex, into the Room of Hidden Things at Hogwarts, on what Harry presumed to be October 31st, 1981. He turned for one last glance at the vortex that had spit them out, but it had already disappeared.
"Well, that was interesting!" exclaimed Luna, "Do you think the Ring was powered by heliopaths?" Harry didn't think heliopaths had anything to do with it, but his skin did feel raw and painful all over, as though he'd just bathed in scalding water.
He glanced down at his hands, concerned, but they weren't actually red, despite how they felt. Next, he turned to his companion, taking in her appearance. She was naked as the day she was born, but she too didn't seem to be burned. She also didn't seem to be at all perturbed by the fact that the layers upon layers of cold weather garments she'd been wearing in Antarctica had disappeared—or perhaps burned up—at some point in transit. As for Harry, his own clothes hadn't fared any better, making him incredibly grateful that he'd opted to wear the Invisibility Cloak and that it—along with the Elder Wand and Resurrection Stone—had survived the journey.
"I'm going to try to find myself some clothes," he said, averting his gaze from his travelling companion's nudity.
Once he'd put enough distance between himself and Luna, so as to not be able to inadvertently catch sight of her bare body—he really didn't want to think about Luna naked—Harry cast a general Summoning Charm, to locate some clothes in the maze that was the Room of Hidden Things. Quite a few items responded to his Accio, and he managed to piece together a half-way decent outfit for himself and, while he was at it, set aside a few items for Luna, in case she still wasn't dressed when he got back.
She wasn't. However, the fact that she was still completely naked might not have been entirely her fault. She probably hadn't been able to locate any clothes in a timely manner—assuming that she'd looked—without her wand, which had not survived the trip. So, Harry stifled his sigh of exasperation and, instead of asking whether she was planning to get dressed anytime soon, thrust the pile of clothes he'd collected in her general direction and said, "Here, I found you some clothes."
She took them from him but, rather than peruse them immediately said, "Oh, but it's such a relief to be finally free after all that heavy clothing! Why do I have to get dressed right away? It's not like I can come with you to—" she paused, searching her mind for the location in question before giving up, "—wherever it is that your family is hiding. I might as well wait for you here."
This time Harry did sigh. "You can't just lie around naked, Luna. You're supposed to meet my parents in the Shrieking Shack to explain things, since I probably won't have time to." When she still made no move to get dressed, he added, "If you hurry up I can take you under the Cloak; the Shack is as good a place as any for me to Apparate from."
"Fine," she answered, pouting—or rather, Harry suspected that she was pouting, based on her tone of voice. He steadfastly refused to look her way, until she was fully clothed, even as he heard her begin to riffle through the pile of clothes that he'd handed her.
Once he was sure that she was actually getting dressed, Harry wandered off to give her some privacy—not that she seemed to need it—and to try Summoning a wand for her. None came flying. Apparently, no one had been foolish enough to leave a wand in the Room of Requirement. Then again, he would have been surprised if someone had.
When he returned empty-handed a few minutes later, Luna was fully clothed and had somehow managed to recreate her usual eccentric style of dress from the small assortment of available garments. She didn't seem overly disappointed by his inability to find her a wand. Instead of complaining, she gracefully accepted his apology, before joining him under the Invisibility Cloak, without further argument.
When they reached the Shrieking Shack at the outskirts of Hogsmeade, Harry found himself hesitating. He broke the silence, "I guess this is it... wish me luck?"
Luna smiled at him encouragingly, "Good luck, Harry."
Harry nodded his thanks, and then gathering up his courage, Apparated to the road just outside number 5 Cherry Road. He took a moment to take in the sight of his family home—standing once more but hidden from all but a select few—before approaching. There was no mistaking the exact moment he crossed the ancient blood wards at the edge of the property, but even seventeen years out of time they recognized and let him through.
At the threshold, he hesitated, once more. Though he had imagined this scenario hundreds of times, and imagined dozens of ways the present scene might unfold, he now found himself frozen in indecision, his plans forgotten. Should he enter with his Cloak on or off? Should he attempt to explain himself right away, or Stun his parents first, then explain? Should he explain at all, or simply send them to Luna, via Portkey, despite the fact that it would destroy the wards? Should he not even approach his parents and instead lie in wake for Voldemort and attack the dark wizard before he engaged his father in a wand fight?
Finally, his mind made up, Harry cast a non-verbal Alohomora and slipped quietly through the front door. He watched in silence, for a moment, as his family enjoyed what seemed to be a quiet evening in the living room. Lily sat in a deep couch by the fire, knitting what looked to be a scarf to Harry's untrained eyes. James sat across from her with a book in his lap watching fifteen-month-old Harry, who sat on the floor between them, playing with an assortment of colour-changing multi-coloured blocks.
The longer Harry stood watching, the more he felt like a spy—an intruder in his own home. Finally, unable to take the tension any longer, he pulled off his Invisibility Cloak and cleared his throat, to get his parents' attention. The results were nearly instantaneous. Within seconds of noticing him, both adults had their wands drawn and pointed his way.
Harry dropped his wand and threw up his empty hands in surrender. Sensing the nervous tension in the air, he took a deep breath, and exhaled, preparing to explain. "I mean you no harm," he began, "I came to warn you. Voldemort—" A silent Stunner caught him by surprise mid-sentence.
When he came to again and found himself magically bound to a chair, Harry attempted, unsuccessfully, to quash the panic that was slowly rising in him. Why hadn't his parents let him explain before tying him up? He'd expected them to at least hear him out. How long had he been unconscious? How long did he have before Voldemort showed up? Would things have worked out better if he'd followed Luna's plan, instead of acting on a whim?
Lily and baby Harry were nowhere in sight but his father stood before him, wand drawn. "Who are you?" James asked, his voice hard, "How did you get through our wards?"
Harry, still in a state of panic, ignored the question, "Please, you have to let me go. Voldemort might be here any minute. It's not safe."
"Who are you?" repeated James, more forcefully than before, "How did you get through our wards?"
Taking a few calming breaths, Harry attempted to answer. After his first three false starts, he settled for, "You won't believe me if I tell you."
"Who are you?" James demanded.
Harry took another deep breath and braced himself for the inevitable outburst, "My name is Harry James Potter."
The sputtering rage with which his father reacted did not disappoint. He didn't curse Harry, but definitely looked ready to do so.
"Please, just let me explain," Harry continued, "I know that I have no way to prove it, but hear me out. I just walked through the Fidelius Charm and the ancient Potter blood wards without raising an alarm. I have my mother's eyes, and my father's hair and nose, and I arrived in Ignotus Peverell's Cloak of Invisibility, which has been passed down through my father's family—your family—for generations."
"My son is fifteen months old. You are not my son. I don't know how you stole my cloak from Dumbledore, or tricked the blood wards, or what you did to Peter to get him to reveal our secret, but you will tell me!" James yelled.
"Please," Harry pleaded, "Voldemort knows your location, and is going to attack here tonight. I travelled back through time in order to warn you; to evacuate you to safety while I take care of him."
"A likely story."
Harry sighed. Somehow in all his considerations he'd overlooked this possibility. Why had he thought that his parents would welcome him with open arms? Luna had warned him that they probably wouldn't.
"Please," he tried again, "I don't want you to die. I came here to prevent you from dying and leaving baby Harry an orphan to be raised miserable and abused by Vernon and Petunia Dursley and being turned into a martyr by Dumbledore." Harry was vaguely aware that he was babbling, but his mention of the Dursleys seemed to have gotten James' attention, so he continued, "I'm the only one that stands a chance of vanquishing him. Please, Dad."
He took it as a good sign that James didn't immediately start yelling at him again, but as the silence following his statement grew, Harry found himself attempting to wandlessly free himself of his bindings—both magical and physical. The odds of him escaping his bonds and overpowering his father were decidedly low, however—particularly with James' wand trained on him. He also still hadn't seen or heard Lily, since she'd Stunned him. Was she hidden just out of sight, ready to assist James, or had she retreated to the relative safety of the upstairs floor with baby Harry?
James had yet to make up his mind when his eyes suddenly widened in disbelief; both he and Harry felt the moment Voldemort began tearing down the outer wards.
"It's him!" said Harry, "We're out of time! Untie me, and get your wife and son out of here, before we all die!"
James appeared to hesitate for a moment more, his mouth gaping in shock, but he did free Harry.
The younger wizard ignored the mutter of, "I can't believe that I'm trusting you," as he reclaimed his wand and quickly pulled the Invisibility Cloak back on.
"Go! Run!" Harry repeated. When James still seemed in no hurry to flee, he added, "Get yourselves to the Shrieking Shack. I'll meet you there," hoping that he'd be able to keep his word. So much had gone wrong already that he was no longer sure if he'd be leaving Godric's Hollow alive. Thank goodness Luna had stayed behind; she'd be able to warn the Headmaster about Voldemort's Horcruxes if he didn't make it back.
James disappeared up the stairs, just as Voldemort blasted his way through the front door. The Dark Lord paused to cast a detection charm, and locating the home's three known inhabitants on the second floor, headed towards the stairs. He didn't notice Harry—hidden from more than just sight by Ignotus Peverell's Cloak of Invisibility—even as the younger wizard snuck up behind him, wielding the Elder Wand.
Harry opened his mouth to incant the Killing Curse, "Ava—"
Voldemort spun around in surprise—much quicker than Harry had anticipated—and blasted a silent curse in his general direction, before Harry could utter more than the first syllable.
Harry threw himself to the ground—just in time—as a flash of sickly yellow light zoomed through the space he'd previously occupied. Fragments of wood and upholstery went flying as the curse shattered the armchair James had been sitting in earlier that evening.
"Avada Kedavra!" Harry tried again, rolling right to avoid another curse from Voldemort.
This time the flash of green light hit the dark wizard square in the chest, and he crumpled to a heap on the parlour floor, a look of astonishment on his face.
Harry stared in disbelief—and relief. Relief that he'd not been hit, disbelief at his success… While he'd been on the receiving end of more than his share of Killing Curses, it was the first time he'd actually cast one himself. Could it really be that simple? Was he really the first person to actually hit Voldemort with a Killing Curse?
The relief lasted only a minute. He knew that it was an empty victory. Five sixths of Voldemort's soul still needed to be hunted down and destroyed...