A different take on what decisions Chuck and Sarah could have made in "Meus lux lucis". The Latin, Quidnam Vos Es, mean "Who You Are". There are several differences between the timeline in this story and the one in Meus lux lucis. So don't expect everything to be exactly the same. Also, the idea for a possible third part to this story is bouncing around, so let me know what you think!

Quidnam Vos Es

Chuck was fuming.

And his hand was throbbing.

This couldn't be real. After everything that had happened in the last six months – and now this, now Shaw. He didn't know what to do or where to go. He couldn't go back to Sarah, she was the reason this was happening.

He couldn't go to Ellie or Morgan – that would be too long of a story.

But really Chuck just wasn't ready to admit what was happening to himself. It seemed like every day brought a larger wedge between him and Sarah. And now Agent Shaw was there at the perfect time to take Sarah away from him.

"Hey."

The voice startled him, but he should have known she wouldn't just let him run, not after what had happened.

"What's going on?"

"I think the better question is what you're doing here."

"Where are you going Chuck?"

"Away from here. I thought you would have figured that out, Agent Walker. What with the packed bags and all."

He couldn't stop the ice in his voice even if he wanted to. After all, who expects to lose the woman you love just a few weeks after you tell her you love her? A woman you never had in the first place and never will.

He didn't miss the way her eyes shut tight at his words though, or the shiver that shook her body.

"Chuck will you at least let me explain? You can't just run away from everything that's happening. We both know you won't. After all, you wouldn't run all those months ago!"

Chuck could tell he was getting to her. Ever since the train station in Prague, she hadn't yelled at him like this. He knew she was trying to put up an emotional wall - but it was finally falling down. But was it because of him or Shaw?

"Don't do this Sarah. Things change. I'm trying so hard not to say the things I want to. Because I know, I know they'll hurt you. After all this time I still can't do that to you. Even if it seems you don't feel the same way. So let me go. Just let me go."

He knew she wanted to say something, anything to stop him, but the words wouldn't come and he didn't – couldn't – wait any longer. "Goodbye Sarah."

And as he was making his way out he never heard her whispered plea, "But I don't want to…"

*****

Thirty minutes later Chuck was done packing.

Sitting on his bed, Chuck fingered the plain white envelope containing Ellie's letter in his hands. He didn't know why but he couldn't make himself get off the bed. He was finally ready to leave everything behind – or so he thought. But something was keeping him here.

So many things had happened in his life these past few years. For so long he had thought that this life wasn't the one he wanted. And then things had changed - he had changed. But once again everything was spinning out of control and there was nothing he could do to stop it.

This time though, Sarah wouldn't be there to bring him back. Chuck didn't know if that hurt more than anything or not.

Thinking back to before, Chuck was finally calm enough to see how much Sarah was hurting. So many thoughts and feelings were pulling Chuck in every direction – he didn't know who or what to trust anymore.

He couldn't change his mind now – he knew that. But maybe though, for Sarah, he could try and explain everything in his head – and in his heart.

Picking up a pen and paper, Chuck decided he had one last thing to say before walking out of her life forever.

'Sarah, I never thought I'd be the one writing this letter…'

*****

She had spent the better part of two hours wandering aimlessly through Los Angeles.

Sarah walked from Santa Monica Pier to the beach where Ellie and Devon were married. Everywhere she looked, it all reminded her of Chuck. Maybe if things had been different – maybe then she'd been strong enough to tell him how she felt. But how can you tell someone you love them when you don't know what love is?

Finally making it to her doorstep Sarah planned to lock herself in until she figured out what to do. Stepping in, she finally saw the crisp white envelope that had been left under her door. Picking it up she immediately recognized Chuck's handwriting.

His messy scrawl across the front of the envelope sent a shiver through her heart. He had simply written Sarah.

Taking a seat on her bed, she hesitated only a moment before opening and removing the thin sheet of paper.

Sarah,

I never thought I'd be the one writing this letter…

Since the day you walked into my life I knew you were something special. Maybe at first it was just because you were actually talking to me…I don't know. But once I learned what you did…I knew for sure that you were meant for more than the life I could give you.

Even now I don't think I could give you that life. I'm not strong enough. I wish I could though. I wish I could be man enough to accept that I'm not worth giving up everything for.

Sometimes I think I'm just being selfish. After all, if I truly loved you wouldn't I be willing to understand how important this job is to you? Even now…after being a part of your life – this life – for this long, I don't really understand how someone could want this more than love, more than family.

As I sit here on my bed I realized something though Sarah. Maybe this isn't about you and me. Maybe it's not about giving everything up for each other. Ever since you came into my life I've seen that maybe I was meant for more. Maybe I was supposed to have this life. Maybe even with you.

But we can't change the past can we? The only thing we can do is look to the future and make sure that it's everything we want it to be.

The only picture I'm taking with me is one of the two of us with Ellie and Devon. I'm going to look at that picture every day Sarah, and hopefully it'll help make me a better man. Maybe one day I'll be able to go back to Burbank and see you and Ellie again. Maybe I'll be able to tell you who I am. Not who I should have been.

I hope that these aren't the last words I ever give to you. I wish I could tell this to you face to face, but I don't think I'm strong enough to do that yet.

I hope I see you again Sarah. I hope when I do that the first thing I'll see is that smile that I fell in love with.

Who knows, maybe then I'll be willing to give everything up for you, instead of asking for you to do that same. No matter what though, you'll always have my heart Sarah Walker.

I love you.

Sarah didn't know how many times she had read his letter, but she did know that each time had cut a deeper hole in her heart.

*****

Three Days Later…

It had seemed like an eternity since he had left, and every day seemed to only lead to more dead ends in Sarah's search for Chuck. After reading the letter he had left, Sarah had to make a decision – one that would change everything.

There was no hesitation though as she picked up the phone. Contacting General Beckman, Sarah quickly informed her of the situation, saying that she had everything taken care of. Knowing that her actions here would change everything for her and Chuck, Sarah interrupted Beckman as she was finalizing Sarah's order.

"General there is one more thing…if you want me to bring Chuck back there's something that we need first. Two things actually… After 3 years of exemplary work we expect the CIA to turn a blind eye to what Chuck and I do outside of the missions. We both know that Chuck and I can and would work better in the field. Second, Agent Shaw needs to be reassigned. Not only has he caused several of the team's personal problems, he's also only out to further his agenda in regards to the missions he's been a part of."

"Those are serious demands Agent Walker. And although I will be watching you and Chuck very closely I will grant you your requests – for now. But if you don't return with the Intersect intact Agent Walker, or you and Agent Bartowski in any way compromise a future mission, both of your careers in the CIA will be over."

She hadn't expected it to take so long in tracking down Chuck, but three days later and she was no closer to knowing where he was.

Sarah was startled out of her thoughts by her phone. Not knowing where else to look for Chuck, she was relieved to see it Ellie was calling. "Hey Ellie…any word?"

The tense silence that greeted her on the other side of the line sent a chill down Sarah's spine. Something wasn't right. "Ellie…are you there? What's wrong?"

"Sarah…I think you need to come over as soon as possible. It's Chuck."

---

Fifteen minutes later Sarah's car screeched to a halt in front of Ellie's apartment building. Making her way towards the door, Sarah was surprised to see Casey already waiting at the door, with a tear-streaked Ellie standing in the doorway.

Hours after Chuck had left, Sarah had made a decision. After everything that had happened the past couple years, Ellie deserved to know the truth. Especially when it was the reason her brother had suddenly ran from everything he had ever wanted or needed. Ignoring both the General and Casey's protests Sarah had spent the better part of those next five hours telling Ellie anything and everything she could about the life she had shared with Chuck for those two and a half years prior.

Ellie had been, to say the least, upset. Everything she felt she knew about Chuck and Sarah seemed to be a lie. But no one could fake the emotions that showed through in Sarah's every action. All that mattered though was finding Chuck. The rest could wait until he was back safe. Now two days later Ellie was calling Sarah in a voice that shook her to the core. She had never heard Ellie so worried…so scared.

Looking to Ellie first, Sarah didn't know if she wanted to ask the question that was echoing through her mind.

When neither woman spoke up, Casey took it upon himself to break the deafening silence surrounding the group. Turning to Sarah he started, "Walker, there's something you have to know. Before he took off the other day Chuck stopped by Castle looking for me. He wanted me to contact Beckman and have him reassigned... The good news is that she wouldn't reassign him…at least not yet. The bad news is that when I called Bartowski to tell him this was the last time I talked to him. "

"Casey what do you mean he asked for reassignment?! He's the damn Intersect! He can't go off on his own!"

Nodding her agreement, Ellie finally spoke up. "John what exactly did this General Beckman say? Was she willing to ship him off at all? Or not?"

Suddenly a sickening feeling overtook Sarah…what if Chuck had contacted Beckman without one of them present? What if he was on some plane somewhere? Headed god knows where to do something that would forever change him – because of her? Reaching for her phone, Sarah accessed the Castle logs. What she found stole the breath from her lungs.

"Oh my god…" Turning on Casey, she handed him the phone. "What exactly did Beckman say? And what the hell was this mission about?"

Glancing at Ellie, Casey grunted. 'Listen Walker, how about we move this inside my apartment. I'll tell you everything you need to know."

---

A minute later the group had situated themselves on Casey's sofa.

Looking pointedly at Ellie, Casey spoke first. "Anything I say doesn't leave this room. If Beckman finds out I told either of you this, my ass will be on the street in no time - If I'm lucky." At both their nods, Casey took a deep breath. "The gist of it was that Chuck asked for an assignment based out of Germany. He was able to figure out the basics of the mission and decided he could handle it. Personally I didn't think the moron would last a second..." Sarah's warning glance in his direction earned her an eye roll.

"Anyway, Bartowski got Beckman on the phone and said he wanted the Germany mission and that he'd be ready to go within the hour. He left me to arrange the details. He also told Beckman he'd be at the airport whether he received the mission or not. Once he had left though I was ordered to do whatever necessary to keep him from getting inside the airport – and it seemed to work. He hasn't been seen there. Which is why I didn't bother mentioning what had happened. Any other questions Walker, or are you finally satisfied that I have no idea where Chuck is?"

Sarah didn't even bother answering him as she made her way out the door.

*****

It had been three days since he had seen her…and he still couldn't get the look on her face out of his mind. Some part of him wished she would track him down – stop him from doing this. But another part – a larger part – knew he was doing the right thing. The necessary thing.

It was funny how Chuck kept facing these choices. Why was he always forced to choose between Sarah and the greater good? Why couldn't they finally get their chance?

Sometimes it seemed like they never would. And maybe that was best. But staying in Los Angeles any longer would only hurt them. So it was time to leave. Time to leave behind everything he had ever known and loved: the Buy More…Ellie…home. He was finally ready too… he had to be. Checking his watch one more time, Chuck sighed.

Ten more minutes…

Nine minutes later found Chuck pacing the narrow path between seats at Union Station. In less than a minute Ellie would be receiving the letter he had written to her…and in five minutes he would be boarding a train south and going to wherever he wanted from there.

As the alarm on his watch beeped, Chuck could no longer hold in the tide of emotion that had been locked up inside of him for three days. With his head in his hands he fell to the seat, his mind focused solely on his sister, and her reaction to everything, every secret the letter she was reading held.

---

Sarah had barely made it outside the courtyard when Ellie's excited squeal reached her ears. She had paid no attention to Ellie racing after her – or the courier who had tried to gain her attention. But Ellie's exclamation of Chuck's name stopped her in her tracks.

Glancing back, she saw Ellie standing by the fountain, a letter clutched in her hands. "Oh my god, Sarah! It's from Chuck!"

As Ellie opened the letter, the two women moved to sit by the fountain in the middle of the courtyard. Grabbing Sarah's hand, Ellie began to read aloud.

"Dear Ellie,

There are so many things I want to tell you, things that I need to tell you about these past three years. I've been living a lie El. I wish I could share with you everything I've done, or about the things I've seen but it's still not safe. I want you to know that I'll always be there for you and Devon. You may not see me, but I'll always be watching. I promise."

When Ellie trailed off Sarah looked up, and was surprised to look into Ellie's eyes. Not sure what was written next Sarah gently took her hand. Nodding that it was ok to continue Sarah watched as Ellie nodded too…and then began once again.

"I know you're probably confused, this is a lot to take in. But it's only the beginning Ellie. Three years ago I was contacted by Bryce. He sent me a government database full of secrets. Since that day Sarah and John Casey have been protecting me. Don't blame them, please. They're the reason I've been able to stay in Los Angeles all this time. I've trusted them with my life – still do. You can trust them too. No matter what happens I want you to trust Sarah for me Ellie. She's the only one I trust to keep you safe until I come back. And I promise – I will come back. To you, and to Devon, and Morgan. To my family. I love you guys, and I'll see you soon.

I wish I didn't have to leave. But there are some things I have to fix myself before I can have the life I want. Wait for me sis. I'll see you soon.

Love, Chuck"

---

Neither woman spoke as they let the words that Chuck had written sink in.

Unsure of what to say or do, Sarah could do nothing but stare at her hands. She understood why Chuck had written this letter – she honestly did. But now she was here, and he wasn't. How could she explain these past three years to the woman, who had become like a sister to her, without hurting her?

Taking a deep breath, Sarah looked up. "Ellie…I can explain."

"Sarah, listen…"

The woman laughed, and the tension that had surrounded them seemed to dissipate. Glancing at the brunette, Sarah nodded. "Go ahead, Ellie."

"Look Sarah, this is all a lot to take in. We both know that things have changed now. For whatever reason though Chuck thought now was the time for me to learn everything. And as much as I wish he…the both of you trusted me enough to tell me about this from the start…I get why you couldn't. And even though we will talk about all of this one day, there's something I need to tell you first. No matter how hard you and Chuck may have tried, I could always tell that there was something real between the two of you – even if you denied it to yourself."

"Ellie…"

"No Sarah, just listen. Chuck trusted you. I trust you. But I need you to do something for me first." Handing Sarah the paper, she pointed toward the bottom before continuing. "I can't just sit here and let the two of you throw away something amazing because the two of you were too scared to admit how you feel. And as much as I want to be the one to bring Chuck back, somehow I get the feeling you're the only one who can fix this."

Looking at the paper in her hands, Sarah couldn't help the smile that appeared as she read the last line written on the paper. Turning back to Ellie, Sarah wrapped the older woman in a hug before grabbing her jacket. "Thank you Ellie. So much." And then she was gone.

Picking up the paper that Sarah had left behind, Ellie read the message one more time.

"If you get this in time…I'm leaving from Union Station on the 7:15pm train to LAX. I hope I see you there."

*****

7:05pm Union Station

Racing through Union Station, Sarah finally allowed the gravity of what she was about to do sink in. Was she really going to stop Chuck? After everything they had been through would it really work this time? Could she risk not even trying?

After stopping to find what platform he'd be on, Sarah slowed down and took a moment to figure out just how much she wanted to tell Chuck.

Arriving at the platform Sarah began searching for him, still unsure as to what she wanted to say. Finally spotting his form on the other end she began making her way to him. She was just 10 feet away when he finally looked up, connecting their eyes. As soon as his eyes met hers though he looked away, unable to disguise the look of anxiety that crossed his features as he did so. Discouraged, Sarah didn't move. Instead she took the time to take him in. From his unruly curls to his signature Chuck Taylor Converse high tops.

Sarah didn't know how long they stood there, unable to look each other in the eye but it seemed like an eternity when in reality it was barely two minutes. And then for one brief moment their eyes connected again - and in that second she knew what she had to do. That it was the right thing to do.

Before she knew what was happening, Sarah was face to face with the man that had become more important to her than anyone ever had before.

Before Chuck could say a word, Sarah grabbed his hand and led him back to the benches lining the middle of the platform. Releasing Chuck's hand, she turned to watch as people passed before them. "I'm sorry. I'm sorry everything went wrong…for the way I acted after Prague. I'm sorry it took me so long to realize that you're everything I've ever wanted. It's just…the CIA is the only thing I've ever been good at. A part of me is still scared that this won't work… that I'll lose you. But I'd rather have whatever time I can with you than none at all."

Turning back to him, Sarah grabbed his hand once again. "Chuck I've never been good at opening up. But when I thought I had lost you…it made me reevaluate what was important to me."

Finally looking at Sarah, Chuck spoke for the first time. "What are you saying Sarah?"

"What I'm saying is…I'm ready. I'm ready to try and be everything you want and need me to be Chuck."

Neither spoke for a moment, could only watch, as their hands remained entwined. The world continued to spin around them though neither noticed.

"You know, three years ago I never would have imagined we'd be having this conversation. Let alone twice. But I do know one thing Sarah. We can't go back. I can't go back. Not to the way things were before. As much as I want to, my heart isn't strong enough to go through this again."

"I know that Chuck…I do. After everything that has happened, I'm not as strong as you think I am. These past few months have been some of the hardest…even after everything I went through with my father and the CIA. And it was because you came into my life and showed me that it was ok to have feelings, it was ok to need someone. And even though I might not always show it, and I'm not the most eloquent sometimes…I need you Chuck. Always will."

Before Chuck could respond, a mechanical voice echoed through the platform… "Final call for the 7:15pm train to LAX. Please have your ticket and identification ready. Thank you. For the last time… Final call for the 7:15pm train to LAX."

"What should I do Sarah? Tell me what to do to make everything right."

"I can't tell you that Chuck. I wish I could tell you to stay because it's what I want. But I won't do that, because as much as I want that I'm not sure it's what's best for you. You have to make this decision on your own."

"Sarah…give me a reason to stay." She knows what he's saying. Deep down she wishes he'd just say it. Feels like it would mean more if he said it aloud. Tell me you're my reason to stay.

"I quit. I told Beckman I couldn't do this anymore because it wasn't what I want. I don't want to save the world when it costs me the one person who has become my world."

"Sarah… these past three years have been amazing. Everything we've done…I never dreamed I could be a part of something like this. And I'm not going to turn my back on that, on you. But I can't just forget everything that's happened. I almost left Sarah – because you hurt me. As much as you mean to me…my heart may forget but my mind won't. I need time to be myself again. But I will always be there when you need me. Just maybe not the way you want me to be."

Sarah could only nod as Chuck finished. She didn't know what to say… What could she say? He was right. And now she has to live with that. And she will – for however long it takes for him to open back up his heart and his mind to her.

She says the one thing that he needs to hear… "As long as you're still here Chuck…I can do anything. Friends?"

The grin that crosses his face tells her that everything will be okay. One day everything will be the way it should. But until then they'll take what they can get.

Taking his outreached hand, she nods. "Friends."

Maybe, just maybe…it won't take as long as she thinks. "Let's go home, Chuck."

"Yeah. Let's go home."

The End.