A/N: forgot to mention, this story was written to two songs from the Armageddon soundtrack, AJ and Short Straw, in that order. In case you felt like having some mood music for this one. (AJ is a little all over the place, but I put in the cue for short straw. Because I could. ; )

Miscalculation

"Percy, we have a problem." Wheeljack announced as he strode into their lab. Perceptor glanced up from his terminal with a wry, tired smile.

"The statistical odds of there being a problem at any given time have been increasing at an extreme rate due to our recent circumstances." he noted. "However, the ratio of difficult situations being presented to you admitting such to be 'a problem' is relatively quite low. So tell me, how dire is the situation at this point?"

Wheeljack sat at the main terminal and inserted a data chip. Codes flashed across the screens. "Prime needs us to finish the Reflector project's calculations and design phases so we can get right to building and implementing in Iacon Central's workshops."

Perceptor scanned the information on the screen critically.

"Three queries, my friend; why would we transfer all our work to Central when the device can easily be completed in our workshops here, and if I am not mistaken—and I'm not—this is Datum's calculations and coding for his part of the project, but they appear incomplete, and we planned on having him present for the testing and finalizing, yet he is not. What has detained him? Finally, I am failing to see this as your typical problem situation, leading me to conclude that there is more to it than you have divulged so far." Perceptor looked down at his fellow inventor expectantly, but Wheeljack didn't look back.

"I was getting there. Datum and his assistant can't be here because they've been deactivated." Perceptor's optics flared brightly in shock. "The Decepticons somehow located their lab and razed it with the two of them still inside. They managed to save this to the back-up file, which was recovered and delivered to me by Ultra Magnus himself just a breem ago." Perceptor sat in the second chair, optics dimming in disappointment and worry at the news.

"How could this happen? Datum's security was just as advanced and close as ours, how could they find him? And why is Ultra Magnus here?"

A knock at the door drew their attention for a moment. "Enter." Wheeljack called. The door slid open to reveal Springer, heavily armored and hefting a serious looking piece of artillery.

"We're all set up out here, Jack." The green Wrecker informed him. "We'll keep you posted, but Magnus' got some tremors already, so we'd appreciate it if you guys hurried as fast as you can." Wheeljack nodded.

"Thanks, Springer. We'll try. Good luck."

"You too."

The door slid closed as the Wrecker trudged off to join his team and Perceptor turned back to his friend with slightly paler optics.

"Shockwave is moving in, isn't he."

"'Fraid so, Percy. Jazz lost one of his best agents just a Deca-orn ago with no warning. He thinks we've got a leak in the scientific community and he's trying to snag it before it gets too bad, but the damage has been done. They know where we are, and we have to get this lab work finished before they get here—or before they get through the Wreckers. Whichever comes first. So we have a few joors, tops. Think we can do it?"

Perceptor ran hundreds of calculations through his highly developed processor in the matter of a few astro-seconds before answering. "Our odds are exceptionally small." he said doubtfully. Wheeljack grimaced.

"I know." He agreed. They both studied the data for a contemplative moment.

"But yes. I think we can."

Wheeljack looked up in surprise. A smile tugged at his faceplates. Percy was thinking against the grain of logic? That was a novelty. Perceptor looked down and met his optics firmly.

"I believe we have no other option."

That sobered the engineer pretty fast. He nodded, matching his partner's stolidity. "Then we'd better get to it."

The work was split evenly in an automatic, wordless routine, both completing formulas and programming, running numbers and calculations until something needed testing. Their facility was already outfitted for the trials they needed to perform, and things were clipping along at a good rate. Or so they thought.

The first indication of battle was a slight tremor in the floor. It was still enough to catch both scientist's attention and the lab stilled as they listened. They could hear nothing through the reinforced walls, but a very short, static filled comm. confirmed a moment later that the Wreckers had been engaged.

"Don't worry about us." Springer ordered. "Just do what you gotta do. We'll hold them off as long as you need us to."

"We'll hurry. Take care of yourselves." Wheeljack replied. He turned back to his test. "Percy, we need this to work. Soon." He told his waiting companion.

"I understand, Wheeljack."

They slipped back into their routine of calculating, formulating, checking and rechecking, testing and modifying. The process was long and intense, absorbing their entire processors and almost causing them to forget the battle raging outside their fortress. But the sense of urgency was never lost. Test after test took place on the ground-breaking technology they were pulling together. It would give them the last edge they needed to escape the planet without detection, to hopefully find the All-spark. But none of the tests yielded the results they needed.

"Why isn't it working?" Wheeljack muttered in frustration as the results scrolled past. "The energy out-put in-put is reversed, why? This has to work. It has to." Perceptor shook his helm wearily. Neither of them had gotten any recharge for the last two orns and it was impairing their ability to process well.

"Perhaps we are missing something." He suggested. "We should break down and recheck the formulas again."

"There isn't time for that!" Wheeljack slammed his fist on the keyboard.

"Then what do you suggest?" the normally cordial mech snapped back.

"I don't know. But we're running out of time! The Wreckers just pulled back into the fortress." He admitted dismally. Perceptor paused, and then returned to his terminal and started going over coding and calculations again. Wheeljack sighed and joined him a moment later. They just had to make this work. The Autobots were depending on them—more immediately, the Wreckers were depending on them. This had to work.

An explosion, close enough to hear and feel, shook their inner sanctuary again. This time they didn't pause, but Wheeljack asked after a report from Springer again.

"We're holdin' our own." Springer grunted, explosions loud in the background. "It's a tough little place ya got here. But we're a few mechs short now, might have to pull back again soon. Just focus, Jack. We'll keep 'em off your backs."

Wheeljack turned his attention back to the screen and stared blankly, processors grinding in exhaustion. They had been at it for almost five and a half joors now and he didn't know how much longer he could handle it. But then he shook himself. They need you to focus, he reminded himself. So do it.

Sounds of battle started leaking in as soon as the Wreckers fell back to the second defenses. The tension in the lab grew steadily as they made slow progress over the next half a joor. There was nothing they could do to stop the Decepticon advance and they worked desperately to locate and figure out the problem so they could all escape with their lives and the working formulas that were so important. They were met with more disappointment for over a quarter of another joor until Perceptor calmly announced, "I believe I have located the defect."

The hurdle was jumped, but they still had to run through the rest of the coding and alter it accordingly. Invigorated with the hope of victory, their fingers flew over the keyboards. They were almost done and ready to test when their door shot open so a Wrecker could deposit two injured comrades all over their floor. He worked with a single-minded intensity, ignoring the two staring inventors as he tried to pull his fellow Wreckers back together well enough to get back out and fight.

Wheeljack and Perceptor exchanged a glance. Then they turned to their work without any further allowance for distraction, ignoring the battle at their doorstep in favor of the test they desperately needed to succeed.

In the control room, the small device warmed up.

"Energy levels look good." Wheeljack reported, optics bright in anticipation. Light streamed out the top of their creation and spread to form a dome around the device and it's small table. It was the furthest they had gotten so far and they both felt their sparks jump with hope. It was so close…

But then something went wrong and the stream of light wavered and went out, the dome disappearing. It was great progress, a wonderful leap in functioning, but they had so little time to fix it if they wanted to make it out alive.

"Run the test once more, Wheeljack." Perceptor requested.

"What for?"

"Please, just run the test."

Wheeljack vented doubtfully, but complied. The Reflector project warmed up, light flowed from the top, and a dome was established. And then something amazing happened; the device and its pedestal disappeared. The rest of the test ran and they couldn't detect any light or noise from the spot where their project had been.

Which was exactly what they had wanted it to do.

Wheeljack smiled at Perceptor in excitement, hardly able to believe it was working. Perceptor watched the empty control room, relaxing as relief washed through him, but then glanced at the ground with what looked like regret, or maybe guilt.

I was acquainted with Shockwave before the war." The other scientist said quietly. Wheeljack cocked an optic ridge in confusion. "We worked on several projects together at the Academy." Behind them, another body was thrust into the Wrecker acting as medic's arms already half deactivated. "He was such a logical mech; I rather enjoyed working with him." Wheeljack grabbed Perceptor's arm and pulled him back to the terminal, hardly wobbling at the explosion that shook the entire building.

"You must be really tired. Reminisce after we download this data and get to Iacon Central, okay Percy?"

Perceptor nodded, hurrying to his terminal and beginning the download with that same, regretful expression in his optics and a small frown pulling at his faceplates.

We did it, Springer, we got it! We can get out of here through the tunnels as soon as we set the self-destruct." Wheeljack yelled over the comm. excitedly. Another blast rocked the lab and all he received was static.

(Short Straw) "Springer?" He felt a chill. Were they already too late for him? How many Wreckers were still on-line?

"Right behind you, Jack." came the tired answer. Perceptor and Wheeljack turned to see the once-green mech lowering a blown apart chassis to the floor. It was barely recognizable as having once been Ultra Magnus. Wheeljack's spark went cold. Too late. For Ultra Magnus and Primus knew how many more.

"How long do you need?" Springer asked, optics dull.

"Only ten more astro-seconds." Wheeljack's finger hovered over the self-destruct command as the files finished downloading.

"Complete." Perceptor said.

"Wreckers, pull back to the lab." Springer ordered. Wheeljack initiated the countdown, snatching the data chip, and hurried to grab and subspace the prototype before heading to the closet where the emergency exit to the underground tunnels was. Perceptor was close behind.

"I thought he would still be that way, Wheeljack. I thought, since Megatron was gone, perhaps he could be reasoned with."

Wheeljack threw open the trapdoor. "Are you still going on about Shockwave?" he asked distractedly. Then he processed what his comrade had said and stopped, whipping around and opening his mouth to clarify. Before he could, Perceptor knelt down beside him, grabbed his hand and pressed his data chip into it.

"You must get this to Optimus Prime. Let nothing stop you, Wheeljack. It was through my contact with Shockwave that they must have discovered our location, despite my precautions. I never intended for this to occur, 'Jack, please believe me, but I made a miscalculation and if any other creature is going to perish because of it, it will be me. I am sorry, Wheeljack. Please tell Prime and the other officers that I am so very, very sorry."

Wheeljack gaped at him, processor drawing a blank on the concept. Perceptor would never…he wasn't…well, he was Perceptor for Primus' sake, how could he have…

Springer pushed into the closet and the explosions were right outside the lab door. "Time to go, bots." He announced. Perceptor stood and faced the Wrecker.

"I am remaining behind."

"My orders are to get both of you and the project to Iacon Central." Springer shot back. "This is no time for heroics."

"I am remaining behind." Perceptor reiterated in his no-nonsense voice. Another detonation shook the walls, drowning out the self-destruct countdown for a moment. Perceptor stared slightly down at Springer and Springer stared back. Wheeljack stared blankly at the data chip in his hand, and then up at Perceptor.

"You can't…" he started, voice faint.

"We don't have time for this. Do you have the project, Wheeljack?" Springer interrupted.

"He has the files." Perceptor confirmed. "Thank you, Springer."

The Wrecker gave Wheeljack a shove. "Get moving, Jack." He turned and offered a rifle to Perceptor. "Here, take this." Wheeljack caught himself, starting to panic as the reality of the situation sank in.

"You can't do this, Perceptor! We need you!" he blurted.

"Move, Jack! We don't have time!" Springer shoved the engineer again and Wheeljack half fell into the tunnel below.

"Goodbye, my old friend." Perceptor said sadly. Springer and four Wreckers jumped down after him in quick succession and drug Wheeljack away despite his struggles and objections.

"Perceptor!" he called back to his best friend. His answer was the sound of the trap door slamming closed.

Perceptor locked the exit and closed the closet door behind him. The lab door bucked with the force of another blast. The computer beeped out its countdown. Perceptor sat in the chair at the main terminal and turned to face the failing defenses. He had never used a rifle before, but it was simple enough. He situated the weapon in his lap so it was aimed for the door and sat back calmly to wait. The computer counted five astro-seconds to meltdown.

The last explosion blew in the door and a lot of the wall around it. Perceptor didn't blink and opened fire before the last piece had fallen. The computer counted two astro-seconds as return fire flooded the room and Decepticons dove through the opening. Three shots found the scientist before the computer counted to one, but he didn't move or seem to notice.

The initiation tone for self-destruct was quiet compared to the artillery fire, and only Perceptor heard it. He off-lined his optics and leaned his helm back, looking relaxed but keeping the trigger wide open.

Till all are one." He murmured.

The computer he had built and worked at for the last few hundred years exploded, and the flames enveloped him like the warm arms of a divine being he had once heard about, long ago…

Safely away from the explosion, Wheeljack watched the disguised laboratory collapse in on itself, taking most of the Decepticons and his friend with it.

Goodbye, Percy." He whispered. Springer put a hand on his shoulder and they walked away from the ledge.

"They died honorably—every last one of them." Springer said quietly. A blue Wrecker hummed agreement with Wheeljack, the other three glanced away or stared blankly at nothing. "Roll out, Autobots. We need to be at Iacon Central ASAP." The other Wreckers were quick to fall to their alt-modes and head off down the tunnels again.

"Out of curiosity, do you know why Perceptor wanted to stay behind?" Springer asked Wheeljack as they trudged back into the underground of Cybertron. Wheeljack looked down at the data chip still clenched in his hand.

"He thought it was his fault this happened…but he was wrong—it wasn't anybody's fault. He shouldn't have sacrificed himself. I wish I'd had more time to convince him…But it doesn't matter any more." And Wheeljack transformed down into his alt-mode and drove away.

Perceptor's was a hero's death and his record was perfect. Nobody was going to speak out against that. Especially not Wheeljack.