A/N: NOwn Chuck. I made a new word. As David Carner would say, 'you're welcome, Websters'.

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Sarah got the call from Graham around dawn. The sun was fully up by the time she made it to the wreck in the hills. The car was burned out with just a charred shell left. She smelled burnt rubber and scorched metal. A light wind blew the brownish-yellow dust around. It was going to be a hot day. Cops and crime scene techs swarmed around the car taking pictures and making measurements. Other cops were canvassing the area looking for witnesses.

How could this be?, she asked herself. Only she and Casey knew Zarnow was coming to Burbank to see his patient. Secrecy was extreme. Not that many people even knew about the Intersect project. Who would benefit from killing Zarnow and keeping Chuck the Intersect? As she was mulling these questions and examining the scene, her toe nudged a destroyed cell phone. She recognized it as an NSA incinerator. Oh shit. An assassination tool used by Casey and his people. Leaves no biological material behind. Everything organic burned up. Why would Casey kill Zarnow? Is a motive even pertinent? It's Casey. His reputation was well known. Stone cold killer. 'Cold school' was how Graham had described him.

And there he was on the other side of the car, looking at her. She put the incinerator in her pocket.

"Well," she said, "no sign of anything here." The light wind blew her hair into her eyes, but her face was a careful mask. Casey could see the sudden wariness in her blue eyes

"Looks like we are sending the good doctor home in an ashtray," he said with his trademark gruff humor.

"I've got hot dogs to fry."

"And I've got some toasters to sell," he said.

She got into her car and drove away.

Casey took out his phone and called Beckman. "Yeah, Zarnow's dead. Looks like the Intersect stays with Chuck...They want us to think it's a CIA job...No. Absolutely not...Sure, I'll let you know."

In her Porsche, Sarah called Graham. "Graham, secure."

"Walker, secure. I found an NSA incinerator at the site."

"Oh, shit...Does Casey know you found it?"

"I don't think so."

"Ok, show it to Chuck and see if he flashes anything. In the meantime, don't Let Casey know you know. I have to figure out what's going on from here."

"Right." She hung up.

Sarah was kicking herself that she had allowed herself to be lulled into trusting someone like Casey, even for a moment. She knew better than to trust. It was not just a lesson she's learned as a spy, it was a lesson she'd learned her entire life. And Casey's reputation should have put her on notice that trusting him would be a mistake. Fool, she said to herself bitterly.

She hoped Graham could figure out what was going on, but had to admit the possibility that Casey was free-lancing with this hit. Maybe rogue. Maybe just an out of control killer. Maybe he didn't like Zarnow's face or attitude. Sarah couldn't blame him for those, as she didn't like them too much either. If the orders didn't come from Beckman, this situation was even more dangerous.

She drove directly to the Wienerlicious, changed into her outfit and texted Chuck. COME HERE ASAP PLS

A few minutes later he came into the store. She looked serious, even angry. "What's the matter?" he asked, giving her a quick kiss. "I mean, good morning. You look lovely. What's the matter?"

"Zarnow was murdered soon after leaving us last night." Chuck tried to reconcile the harsh, shocking words with the pig tails and borderline comic outfit she wore. It felt bizarre to him.

"What? Oh, God. What happened?" His shock and bafflement were as plain as day.

"Take a look at this." She slid across the counter a plastic baggie containing the incinerator.

Looking at the broken and burned cell phone, he said, "It's a nasty..." Chuck flashed and said, "NSA Incinerator. Special issue. Designed to eliminate all biological traces." He dropped it on the counter as if it had burned his fingers and said, "That's what killed the doctor."

"Exactly. I don't know why, but Casey killed him."

"Why? Why would Casey do that?"

"He's a killer, Chuck. It's what he does." Her voice was harsh, uncompromising.

"Maybe. But all spies kill. This one, though, it's not Casey. There's another explanation. There has to be."

Sarah's voice softened somewhat. "I know you want to believe in him, to trust him...we're a team and all that...and I know this is hard on you... but he's a killer. He and I were the only people who knew Zarnow was coming here to see you. This is a signature NSA device. There is no other explanation. I need you to go back to the Buy More, but don't meet with him alone. Act like you know nothing. You can do that. Trust me, Chuck. Then after your shift is over today come over to my place and we'll figure out what to do next."

With a quick kiss good bye, he turned to leave. He stopped in the doorway, his face troubled, and said, "I still think you're wrong."

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She had changed out of her Wienerlicious outfit and wore jeans and a tee shirt. Sitting on the edge of the bed was a fully loaded H&K MP-5 9mm submachine gun, with the safety off and a long silencer attached. There was a faint whiff of gun oil in the air. It was an ugly weapon, but very effective.

At his knock, Sarah let Chuck into her room. He was still in his Nerd Herd uniform and wore his computer bag slung over his shoulder. "Hey," he said. They exchanged a quick kiss.

"Hey," she said as she checked the corridor in both directions before closing the door.

As he took off the computer bag, he said, "We have to talk about Casey." He saw the weapon on the bed and visibly paled.

"Yes," said Sarah, "We do. I know you don't like this." She gestured to the MP-5 on the bed. "... but it's to protect us. I don't understand what is happening right now with Casey, but I'm not going to let anybody hurt you...or me, for that matter. I know you aren't comfortable with this turn of events. I know you want to think the best of Casey, but you have to trust me."

"I do trust you. I trust you 1000%. But that doesn't mean you're never wrong. It doesn't mean you will win every argument we will ever have … well, to be honest you will probably win most of them," he said with a tiny smile. "I'm allowed to disagree with you and still trust you. If you think otherwise, you and I have very different meanings of the word."

"Of course, I don't' think otherwise, but we both know you are new to this world. Things happen here that you won't be used to. There are betrayals..."

"Please don't tell me I'm not used to betrayal. My mother left when I was little and my dad when I was just a few years older. My buddy got me kicked out of college and started to sleep with my girlfriend, who dumped me at the same time. I am very, very used to betrayal. It's my middle freaking name." He didn't raise his voice, but spoke with deep emotion and pain. Pain that moved Sarah deeply. "But the response to that is not to close yourself off. You have to trust people."

Sarah began to pace around the room. She was clearly struggling with this conversation. "No, you don't. Not in this world. Trusting people...opening yourself up to people, is exactly the way to get hurt. To be betrayed. Look, Bryce betrayed us both...you at Stanford and me just a few months ago when he went rogue..."

"Yes, so the lesson you learn is that your next partner will do the same? That's not much a of lesson."

"The lesson is 'fool me, shame on me." She sounded exasperated.

"That's not the saying and you know it." Chuck sounded equally exasperated. "I'm saying you have to give people the benefit of the doubt. I don't know what has happened to you in your life, in your career, and you don't have to tell me..." He held his hands up in front of him in a defensive gesture. "...but if you assume the worst in everyone you meet..."

"You'll be a hell of a lot safer," interrupted Sarah.

And alone, thought Chuck, but didn't say it. "It's no way to live your life, Sarah," he said softly. "And just for the record, I will never betray you."

"I know that...I know that...That's why...I know you won't betray me. Chuck, you are extraordinary. You are genuinely good. An actual, honest to God good person. You have no idea how rare that is, not just in the spy world, but in the real world too. And to have been burned by so many people...so many important people in your life and still come at the world with the good trusting attitude that you have is incredible. But my experiences have led me to different conclusions." Chuck wondered, if they stayed together long enough, would he ever learn of the betrayals, disappointments and pain that led her to those conclusions. "I don't open up to people." She stopped pacing and put both hands to the sides of her head in frustration. "Not easily...not ever, really. Even this conversation...I've never had a conversation like this in my life...I can't believe I'm having it now, to tell the truth...You seem to have some crazy influence on me. You make me talk about things, think about things...Chuck, I'm not too good at this, at talking about my feelings."

The conversation had clearly gone off on a tangent. And, to make it worse, it was a tangent that upset Sarah. "Well, I don't want to change a thing about you and I don't want you to be uncomfortable. We can come back to questions of trust and the innate goodness of mankind another time, after we've both had the opportunity to re-read St. Augustine," he said with a small smile. Despite herself, Sarah chuckled a little. Chuck had to give her some respite from the heavy conversation they had been sharing. Ha, he thought, let's talk about murder to lighten the mood. "Let's get to a specific example of trust. Casey didn't kill Zarnow."

"We went over this. The incinerator..."

"I know. The incinerator. Do you know how many incinerators the NSA has in Los Angeles? I do. There are five."

"How could you possibly know that?"

"Because while you were away, Casey and I arranged for me to get access to both the NSA an CIA computer systems. I'm an analyst now for both organizations, so I get both clearances. I spent all afternoon trying to figure this out. Morgan covered for me at the Buy More. I assumed that, being a government agency, they would have a log book for their stuff. Governments, bureaucracies, like to keep track of their stuff. They run audits and things like that. There is a log book and I can access it remotely. None of the incinerators have been checked out in the last year. And there is no record of John Casey ever removing one from an NSA inventory, in Los Angeles or anywhere else for that matter."

"But it's an NSA device..."

"Right, so nobody but the NSA has access to it. It's a clear fingerprint from those guys. Except it's not. Eighteen months ago a crate of these things went missing in Houston. There's an ongoing investigation right now to try to find them. The NSA never said anything about it. My guess is because they were embarrassed. Since then incinerators are suspected of having been used in a drug hit in Bogata, the disappearance of a Russian agent in the South of France, and a pretty gruesome murder of a wife and her lover outside of Bangkok. They are floating around the black market right now. I don't even have to use the Intersect to figure any of this out. I just read the NSA files."

"Ok, Chuck, but you're a smart guy. You know all you did is expand the list of suspects. You didn't clear Casey. He and I were the only ones who knew Zarnow was coming here."

"You keep saying that, but it's not true. Casey only found out about Zarnow's visit the same time I did, earlier that day. And really, there were many more people who knew. Both Beckman and Graham knew. Members of their staff probably knew. Zarnow himself knew. God knows how many people he told. The NSA travel office, or whatever, they knew too."

"The Intersect is way beyond top secret. None of those people would know why he was here."

"So? Who says he was killed because of the Intersect? He worked for the NSA a while, right? His murder could have been unrelated to the Intersect. Hell, it could have been a jealous husband. I didn't see him, maybe he was a lothario."

She made a face. "Ok, not a lothario. My point is you made a whole bunch of assumptions to point the finger at Casey. Assumptions that don't stand up to scrutiny. In any event, it couldn't have been Casey. He has an alibi."

"Chuck, you know alibi witnesses can lie."

"Not these alibi witnesses."

"Why? Who are they?"

"Us. You and me. We were with him during the only window of time the incinerator could have been put into Zarnow's car. Right? Think about it. We were in the Buy More when Zarnow arrived. When the test ended, at around 10:30 or quarter to eleven, Zarnow left. You, me and Casey stayed to put the Home Theater room back to normal. We didn't leave until 11:15 or so. By that time, Zarnow was gone."

"You assume he was gone."

"Nope, I know he was gone. According to the preliminary police report, which I also accessed through the NSA, witnesses heard the crash at 11:45 last night. From the Buy More to the crash site up in the hills is at least a 45 minute drive. Minimum. There's no way he was still there when we left the Buy More. He would never have made it to the crash site by the time of the crash. Can't get a better alibi than us, right?"

Sarah stood silently looking out the window for a long time. Hugging herself with her arms crossed under her breasts. Finally, she let out a long sigh. "Right...right...Oh, shit...you were right and I was wrong...I was wrong to suspect Casey. Godammit. How could I have been so stupid? Jumped to that conclusion? Godammit. I'm sorry, Chuck. I was acting like an idiot. Casey didn't kill Zarnow."

She took out her phone and entered a number. "Walker secure...It wasn't Casey... Somebody was trying to set us at each other's throats. ...yeah, it almost worked...Chuck figured it out...No, he didn't flash it, he just figured it out...Yeah, I know...Right." She broke the connection.

She went to the MP-5 on the bed and engaged the safety. Unscrewing the silencer from the end of the stubby barrel, she said, "Graham says we are lucky to have you. He's right. I'm lucky too. Thank you, Chuck." She gave him a kiss and removed the full magazine from the bottom of the weapon.

"No worries, Sarah. It's what partners do for each other, right? Second set of eyes. Talk through thorny problems." She jacked back the slide and ejected the single round she had kept in the chamber.

"Right. Good partners, anyway. So, now that we know it wasn't Casey, how do we figure out what the hell happened to Zarnow?" She took a gun case from the closet and began to put away the weapon.

"I don't know, but a good start is that we do it together, as a team."

He opened the door to the corridor and there stood Casey, still in his Buy More uniform, who said, in greeting, simply, "Walker. Bartowski."

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