A/N: This might not be completely correct with Canon but guess what, its my story and I will post what I want. :-P Also my beta is correctly overloaded with my Big Bang Challenge so this is not beta'd and any mistakes are mine completely.
The mission started out like every other mission, get into the building without notice, get the files, and than get out. Both X5-494 and X5-511 had a spotless record, well outside of the being a twin of the 09ers but that really wasn't something that 494 had in control. The fact that when the pulse hit they were undercover in Dallas, well that wasn't the problem, the problem came when they didn't report in. Manticore was at a loss already, some of the earlier transgenics hadn't taken too well to the pulse and only because of back-ups of back-ups did they save their research.
They had X5's all over the world and unable to contact base, in the first week they lost six agents because they had been unable to contact base and get backup. But 494 and 511, they enjoyed the freedom; at first, the pulse struck and their mission didn't matter anymore. There was no way to contact base, they didn't have in field handlers, time just froze over the entire greater United States and they both rejoiced in the fact. The computer they had been working on shut down, sputtering its last breath before the screen flickered out and the green running like on the tower flickered to a stop. The world around them silent for a few moments before the panic broke out, people could be heard screaming their panic on the ground below and both transgenics had made it out of the building as fast as possible.
Blending into the crowd had been easy, so much panic and worry that no one was paying attention to anything around them, using their training they moved with the crowd, knowing that they should make their way back to base. This was clearly an attack on the US yet not having the means, most cars didn't work, stores were being over run by panic people. There was no way to know just what was happening in the world, they made their way to an abandoned building, or rather semi abandoned because there had been homeless before the pulse even if people liked to think otherwise.
They had made friends easy, a few people offering them blankets or food, both the transgenics using their skills to steal what they could, but after a few close calls with a pissed off store keeper and a shotgun that idea left them, banks were useless and they didn't have much cash on them. As the days pushed on things started to get harder, more people started to make their way in to the city, the confusion wasn't any less and both transgenics knew they would have to make their way back to base, just Seattle was a long ways from Dallas, specially without the use of modern technology.
It was over two weeks before they managed to remake a radio out of spare pieces they had found in the building, it was nothing special but it did pick up the National guard, it was then they found out just what had hit them. An EMP, both of them had been shocked and in that moment knew they had to get back to Manticore, packing up what they had they said a few goodbyes to people who had helped them and left the small building behind, looters and riots already pushing most people out of the city they left before the National guard arrived, they could have put a stop to it but it wasn't their mission.
They hit the road, it was a long walk, perhaps longer then they realized never really having to commit the distance to memory but they knew they could do it. The only problem was the roads wasn't a safe place, perhaps a little safer then the city but both of the trasngenics still looked like young teenagers and that just asked for trouble. They fended people off, managed to actually pick up much-needed objects as they went, it was three days into their walk that they managed to get a pick-up truck after fighting off a little gang.
The trip was much faster and easier after that but then other things started to be a bother, they both knew they could go at least a week without food or water. That wasn't a problem, that they had been given medication that had run out weeks before was. 494 was the first one that had a seizure, 511 could only watch from the driver's seat and worry for who he had started to recall as his friend. Two days later he had one while 494 watched, that night they hit a small little town that had put up walls and after a Mexican stand-off and realizing they were children (it helped sometimes looking so young) had let them in for the night, fed them and let them rest.
The next morning they kicked them out-of-town, but it had been nice to relax for a night. The days turned into a week and it was another two before they finally made it back to Seattle, when they finally arrived it was in lock down. They left their beat up, shot up truck at the border and snuck in, making their way towards home base knowing when they got close enough everything would be okay again. Welcome with open arms, food and meds would be given and they wouldn't have to put up with the humans and their craziness. But when they did arrive it wasn't with so much as open arms as with lab techs, re-indoctrination and tests. Lots and lots of tests, and memory wipes.
Years later they don't remember this mission, claiming their first mission together had been years later than it really was, but the bond that had been forged was still there. Unbreakable and stronger than anything, even stronger than the 09ers, it was something that Manticore could never fix.