Thanks for the reviews! The idea for this fanfic kept spinning in my head, so chapter 2 almost wrote itself...

This chapter will be more ANGST and will contain mature themes, that's why I chose the M rating...

Let the nightmare begin...

During her taxi ride to Broome Street, Paula kept playing with the weirdest ideas in her head. How shall I begin… she wondered… of course I must be very careful, otherwise I will most likely scare him off…. Her biggest trump card, was, however, the photo she had quickly taken. Again and again, Paula couldn't help but stare at the small picture on her mobile's screen. It may not be a master shot, she told herself, but it was clearly recognizable: that little cheater was kissing her doctor. From the angle the shot was taken, one could even suppose that Kate had kissed him on the mouth. Even better, Paula smirked to herself. If this wouldn't convince Rick that Kate Beckett was the wrong woman for him, then what else would?

Soon, her cab ride was over and the driver pulled in. Paula exited the cab hurriedly and made her way towards Rick's building. An overwhelming feeling of perfidious anticipation ran through her veins, showing all over her face and body language. With every step she took towards the entrance, Paula was anxious not to shiver with excitement. The doorman greeted her with his usual politeness; of course, he knew Mrs. Haas was a frequent guest of Mr. Castle, so he saw no need to call him to announce her arrival.

When she got out of the elevator, a decision had been made. Paula's plan how to bear the news to her favorite client was both simple and malicious. As she approached his door, she knocked, first tentatively, but then rather forcefully, impatience now clearly driving her actions…. then the door was finally opened….

Meanwhile, at the hospital:

After Kate had said goodbye to Josh, she left the hospital to grab a bite to eat on her way home. Food cravings had been a frequent occurrence to her lately, and at the moment she was craving cronuts, lots of them. She knew a bakery near her home that made cronuts that were filled with vanilla cream and had a double chocolate icing. Just what I need right now, Kate thought happily, as she made her way to grab a cab.

The ride was short and when Kate entered the bakery, she ordered 3 cronuts along with a big cup of cocoa, take-away of course. No more coffee for today, she thought regretfully. Stepping out on the sidewalk, she stopped walking and, for a minute, considered calling Castle and telling him that she would come home soon. Deciding against that option, she kept walking at a rather quick pace which would take her home within 15 minutes. Just wait and see, Rick, Kate thought happily, this is going to be one of the best days of your life….. If only she knew she was so far from being right….

At the loft…

"Hello, Paula, to what do I owe the pleasure of your visit," Rick inquired rather curiously. Without waiting for him to ask her in, Paula walked determinedly into Rick's living-room. "So, you mentioned some very interesting news, if I recall correctly…? Rick continued his questioning, "What is this all about? And why are you in your gym outfit?"

Shit, Paula thought, I totally forgot about that. It's now or never, this might be my only chance….

"Well, Rick," Paula began cautiously," in life, everything happens for a special reason, don't you agree?" Saying those vague words to him, Paula smirked and tried to look as seriously as possible.

"Yes, sure, I guess you are right, Paula," Rick replied confused. He couldn't read her face. Something about her facial expression told him that there was more behind this, so he asked her: "Paula, please, is there anything special you want to tell me? Because if not, I hope you don't mind if I go back to my writing. The chapter is overdue and Gina will rip off my head if I don't mail it to her within the next 24 hours…. "

"Of course, Rick," Paula smiled knowingly. "Just like ripping off band-aid, I'll do it as quickly as possible: your dear wife, Detective Beckett, is cheating on you!"

At first, he was shocked about her words, but then he started laughing and replied with a firm voice: "Never Paula, you must be dreaming, Kate would never do that to me. So, please, don't accuse my wife of things that you cannot prove!" The last words he almost yelled at her, now visibly pissed off by her accusation.

"Fine," Gina said nonchalantly, "I guess, in that case, I have no other option than to show you….." She began rummaging her bag, when Rick interrupted her impatiently, grabbing her wrists in his hands to stop her. "Show me WHAT?" he asked her somehow insecure, suddenly worried by her confident smile and the way she acted as if she clearly knew she was telling the truth. Slowly, he released her wrists from his grip and let her continue her search, already suspecting he would not like what she was looking for…

Without further hesitation, Paula pulled her phone and searched for the pic she had taken of Kate and Josh. Rick stood still, couldn't help but stare at the image in front of him. The sight of his wife kissing her ex-boyfriend almost knocked him off his feet. Jealousy began to burn deep in his guts, and his mind was suddenly filled with countless emotions….helplessness, anger, despair…..

No no no, this can't be real, he kept telling himself, no, Kate would never cheat on me with Dr. Motorcycle-boy…this must be an old photo…...

"Shocking, isn't it?" , his inner monologue was interrupted by Paula, who did a very poor job at hiding that she was beyond thrilled to present Kate's alleged indiscretion to Rick. "I never thought your current wife would be the cheating type, after all… but then, you never really get to know them, wouldn't you agree? Maybe there is more Nikki Heat in her than you would have imagined…... it's…. so…..slutty, " Paula continued inexorably to pour her venom into Rick's heart.

"I- I know this guy," Rick stuttered," that's Kate old boyfriend. You took this picture today?" he asked her unbelievingly. "Yes, sadly, this just happened half an hour ago, Rick," Paula replied with a fake compassionate smile.

"You should have heard them, Rick, she told him something about having made her happy and hoping you will never find out about them meeting," Paula proceeded her evil charade, seeing how the realization hit Rick hard, his facial expression slowly changing from confused to disappointed, then filled with bitterness, and, finally, cold and detached.

"Oh, my poor Rick," Paula purred, "I hate to be the one that opens your eyes, but I felt like I had no other choice than to tell you…. I know it must be tough, after all that you have done for her…." Saying her alluring words, Paula approached him slowly, dropping her coat and her bag next to the small table in the process and then, when she stood closely to him, she put her hands on his face and said to him in a silky voice: "I would never hurt you like that, Rick, just let me tell you that. She doesn't deserve you. Never has…."

Looking into her eyes, Ricks mind was spinning around…. Hurt, yes the sight of Kate obviously cheating on him with Josh did hurt him, he felt like his heart had just been ripped out of his chest and torn into millions of pieces…. No, he thought, I won't let that happen again. I will never again have a cheating wife see me break because of HER! If I get hurt, so will her….

Without hesitation, he slung his arms around Paula's waist and smirked at her arrogantly: "Well, Paula, I'm sure you know how to take my mind off of this unpleasant occurrence, am I right?" Before Paula could reply, he forced his lips on hers, plunging his tongue into her mouth, his demanding hands groping her body roughly. Just help me forget this has happened, he thought….

"Rick", Paula mouthed breathlessly a couple of moments later, "let's take this party to your bedroom, shall we?"

"Excellent idea, honey," Rick replied with a charming grin, but the smile did not reach his eyes.

Fine, he thought, tit for tat, if Kate cheats on me, I will do the same thing to her. Paula seemed more than willing to help him with this task, so he didn't waste any time and grabbed her hand, heading straight to his bedroom without further thought….

Meanwhile, outside the building:

By the time she had reached her destination, Kate had trouble to balance the paper bag containing the cronuts, the huge takeaway-cup that was filled with cocoa and her bag when she passed the doorman. "Hello, Mrs. Castle, you are coming home early today," the doorman noticed. "Do you want me to call your husband to let him know that you are on your way up so that he can help you with your bags?" he asked her friendly.

"No need, Ernie, thank you", Kate replied with a big smile, "I want to surprise him." After having wished the doorman a good day, she entered the elevator and pushed the corresponding button for her floor. On her ride up, she searched her bag for her keys and the ultrasound picture that her OB/GYN had handed her earlier. Looking at the tiny spot that was her baby, Kate felt joy taking over her and she almost couldn't contain her happy tears. Why do elevator rides always have to take so long? she wondered impatiently. Finally, the elevator stopped and Kate quickly walked towards her doorstep. Oh Rick, she thought hopefully, you will love this….

"Castle, are you home?" Kate called into the loft. There was no reply. He must be in his office, she thought. When she walked past the couch, she noticed a woman's coat and a bag lying on the floor.

I have never seen that outfit on neither Martha, nor Alexis, Kate thought. Without thinking about it any further, she made her way to her husband's office. His desk, however, was empty, the laptop screen displaying its usual screen saver. Kate was about to leave the office and return to the living room when she heard a woman's moan, followed by the moaning of a male voice, one that she would always recognize. What the hell is going on here? she thought. There it was again, this particular sound, it was without a doubt the voice of a woman, and it came straight from hers and Rick's bedroom. Tentatively, she headed towards the bedroom, didn't dare to believe what was obviously going on in there….

As she approached the threshold, she hesitated briefly, closed her eyes, but then forced herself to open them to look at what was going on in front of her. There, on their bed, she saw her husband, stark-naked , lying between a woman's widely splayed legs, thrusting into her forcefully while she was moaning, "Yes Rick, don't stop, it feels so good…" Realization hit her when Kate identified the voice of Paula Haas, her husband's longtime agent. No, Kate screamed inside her mind, shaking her head in disbelief, this just can't be happening…!

Being in shock, she lost hold of the cocoa cup which fell on the floor with a loud thud. The ultrasound pic that she had held in her other hand fell into the puddle of cocoa that was quickly spreading in front of her feet. Surprised at the sudden noise, Rick stopped his actions and looked over his shoulder. Kate felt a shiver creeping over her spine when her eyes met his. There was no sorry, no guilt in his eyes, just bitterness and a cold, calculating smirk on his lips… the Rick Castle she loved and trusted was nowhere to be seen….

"Why…? ... why, Rick… ?", Kate asked, tears coming to her eyes. Without waiting for his reply, she turned around and ran off the bedroom, only to stop in the living room when she heard him yelling his merciless reply: "You are not the only one who knows how to cheat, Kate!"

She had no idea what he meant, but her thoughts were interrupted by a sharp pain that suddenly spread in her lower abdomen. My baby, she thought, then everything faded to black….

Ok... don't kill me. I don't know where this story will go. For now, it doesn't look good for Rick and Kate... reviews, please!