A/N: MINOR REWRITE GET! Thanks again for all your awesome contributions!

Tim allowed his eyes to wander a bit as Fischer led him through the facility and explained the specifics of Project OVID.

"As we all know, the Covenant are an enemy so utterly opposed to humanity that they never take prisoners. They accept no surrenders, no deals, no negotiations. Which makes spying on them a little bit difficult. Sure, we cracked their communication codes ages ago, but they're not always chattering where we can hear them. As a result, our ability to predict them is limited, and our ability to misinform and mislead them is virtually non-existent. I don't have to tell you how much of a problem that is in a war, not being able to engage in information warfare, one of the most important elements of strategy. If we could get even the slightest ability to see inside their operations... it could be the difference between victory and extinction for humanity. But the problem remains: how do you infiltrate an enemy that is so utterly insulated against infiltration, unintentional as that insulation is? Enter Project OVID. Here, we use the latest in biotech, cybernetics, and genetics to create and insert a spy in the enemy ranks. One that they would never look twice at. A Sangheili."

At that, Fischer stopped and turned to look at Tim; it took a moment or two for the latter to realize he was being prompted to speak. "So... you plan to grow a bio-robot or something? An alien terminator?"

"If that were the case, we wouldn't have much need for volunteers," Fischer replied. "No, this is something far more... well, I'd say sci-fi, but we're currently on board an asteroid science lab, so I'll just say strange. We're not making Elites from scratch. We're making them from volunteers."

Tim felt a wave of shock, disbelief, and dark amusement shoot through him. "Species change operation? You're joking. That shit isn't possible."

"You could say the same thing about half the tech the Covenant use, especially the stuff they picked up from the Forerunners. By every metric, according to every known law of physics, none of it should be possible. And yet it is." Fischer gestured for Tim to follow as he continued speaking. "ONI has the best scientists in history. We know everything there is to know about Sangheili physiology, and everything there is to know about human physiology; we know things about genetics that stumped history's brightest minds since the 21st century; even the SPARTAN programs have provided incredible precedent in terms of biological modification. Of course, there's a huge leap from improving the human form to changing it entirely. And that's where the risk comes in."

After some more walking, they arrived in a large room with a holographic display table. With a few taps, Fischer brought up a series of images to provide visual aid as he began to elaborate.

"The transition will involve several methodologies. To start, we'll be utilizing genetic modification and hormone replacement therapy to ease the rest of the process and prevent tissue rejection. As this happens, we'll be performing quite a bit of surgery; using Sangheili stem cell samples, we will grow alien tissue, from bones to musculature to organs. We'll be grafting some of this into you so that your body can do some of the 'alteration' on its own, but most of the work will involve adding to or replacing entire sections of you. You won't be just a clone or copy of an existing Sangheili, which is what would happen if we were to simply grow our own. You'll be yourself, as a Sangheili. Well, minus the ocular implant we'll put in as your 'recording device'."

Tim felt the earlier wave of shock return tenfold, combined with mild horror and severe trepidation. "Have you... done this before?"

"There have been attempts; none of the previous volunteers have survived—and only one even made it to the final stages of conversion. The rest died due to complications from the process. We've learned quite a bit since then, however, and we believe the process is finally perfected. And you wouldn't have been selected if we didn't believe you had the best possible chance of surviving. That being said, there's no way to be a hundred percent sure, and we have at least eight other subjects being prepped as we speak... and it's unlikely that everyone will survive."

"This is... a lot to take in. I see why you didn't explain anything before. But I'm guessing that it's too late to back out of this..."

"I'm afraid so, Private Newman," Fischer responded. "OpSec means none of this gets out. Ever."

A pause came over Tim as he struggled to take in everything he'd been told. "You can change me back afterwards, right?"

"We'll have all your physical records, genetic information, neurological mapping... everything we need to reverse the process. And while it'll still be dangerous, turning you back should be a great deal easier for us than the initial conversion since we'll know a lot more about what the end result needs to look like."

"And... if it kills me, you'll still hold up your end of the bargain, right?"

Fischer smiled. "Absolutely."

The process started out innocently enough; the hormone and gene mods were little more than injections. For the first day or so, nothing seemed different-aside from odd changes in mood and appetite, likely a side effect of the hormone replacement affecting his brain chemistry. By the second day, however, signs of what was to come began to appear in the form of extreme nausea; in fact, that was a severe understatement, but Tim couldn't really find any other way to describe it beyond feeling a regular urge to puke his guts out every hour or so. This was combined with alternating sensations of horrible, bone-chilling cold and blistering, excruciating heat. The first corpse rolled by his room on the night of the second day; it looked normal enough, though he wished it had been covered-the subject's face had been frozen in a permanent expression of agony and horror, silently screaming out their final breaths.

All of that began to seem tame by comparison very quickly, however; the third day was when the surgeries began. Skeletal and muscular alterations were the first wave, along with careful skin grafts. Every second of his waking life was pain, even with post-surgery anesthetic... and according to the doctors, he would soon have to do without, as no known anesthetic would work with Sangheili physiology. Two more corpses, this time covered by thick black material; the only indication of their final fate was hinted at by the misshapen lumps protruding seemingly at random from the far-too-large bodybags. The fourth and fifth days of this were even worse, with horrible joint pain and frequent muscle spasms wracking his form-on top of his previous symptoms from the hormone and gene mods.

By the sixth day, the tissue grafting began to proceed, along with organ replacement. This was the critical moment, where the vast majority of subjects perished in previous experiments. Indeed, the macabre parade of his fellow volunteers being wheeled out for corpse disposal only increased in frequency; by his own count, three or four in on that day alone. By the seventh it was clear that he was the only surviving subject... and he trembled at the thought of joining them. There were moments where Tim felt his life slipping away; one night in particular resulted in him being forcibly resuscitated. That particular night nearly took away his will to continue, nearly tempted him to surrender to the encroaching blackness of death simply to end his suffering. Tim could almost imagine, in that moment and others like it, a shadowy hand reaching out to him, beckoning him towards eternal slumber-and he nearly took it. But something held him back. Kept him from accepting that offer of respite from pain. He wasn't sure what it was; all he knew was that he refused to die. Not like this. Not here, not now.

More surgeries, more pain, and at least two more near-misses. He soon lost count of the time elapsed since this nightmare began; days? Weeks? It all blended together after a while, melted away by the horror of his situation and the resulting agony. As things progressed, however, the pain and spasms gradually subsided, replaced by odd feelings of... disconnection, as if his body were a marionette and he only controlled it with strings. That, too, passed, and over time he felt stronger than he'd ever been. He felt his mood reach some form of equilibrium as well, albeit with a strange sensation of "odd thinking" and "odd emotions" that simultaneously felt worrying and completely natural.

Then, the day of reckoning. Fischer—who had not shown himself for the entire duration of the process—walked into Tim's recovery room one morning with a smile. "It's done. The doctors have cleared you; tomorrow, you go through physical therapy to get used to your new body; it'll likely be another week, maybe a little longer for you to get used to things... but beyond that, you'll be on your own, because you start your mission as soon as that's done."

Tim struggled to speak using his new mouth; he hadn't quite gotten used to it, let alone the deep rumbling voice he'd gained. "Ddoooo... yyyyoou... hhaff... mirrr?"

Fischer grinned, producing a small mirror and holding it in front of Tim.

A scaled hide in a grayish-onyx color. Orange-brown eyes peering out of a narrow skull with the signature squidlike mouth. A stranger, an alien, mimicking his every movement. But it wasn't. Not a stranger. Not an alien. This was him.

"Tim Newman," Fischer said with a smirk, "Meet Tam 'Valarmee."