Bobby Pearson finds himself sitting in the box at the 12th precinct. Just on the other side of the windows is detectives Ryan and Esposito along with their boss Roy Montgomery.

Kate Beckett is looking over the rap sheet for this man wondering how someone who only had two traffic citations for overtime parking and one warning for an illegal left turn was in such a hurry to rush out of The Old Haunt Saturday night

Beckett enters the interrogation room and lays the file on the table before she sits down.

"Bobby Pearson, you have the shortest rap sheet I think have ever seen. Especially for someone who was in such a hurry to leave a bar without settling his tab. Can you tell me why you were trying to leave before you paid your bar bill?"

"I thought you were the IRS or something coming after me for taxes or something. Is that why I'm here? Walking out on a bar tab?"

"It would be if that is all you did. But it seems you were seen last Tuesday flashing a large wad of cash that is out of the norm and I had just wanted to ask you where you got that much money, but instead, you decided to bolt for the door causing the owner of the establishment to stop you from leaving. Can you tell me what that was all about?"

"I…uh…it is not what you think. I didn't do anything. I was just given a nice tip from an

exhibiter at the hotel where I was setting up a display for work"

Hotel? I thought you were a construction worker?"

"I am. I mean I do construction work I build backdrops for exhibit displays or sometimes sets when there is a need for special backdrops"

What hotel were you at, that did you did that special work for?"

"Regents Hotel in midtown"

Beckett is taken back for just a moment "did you say Regents Hotel?"

"Yeah! Why?"

"You work there all the time?"

"No. I am a carpenter and I build backdrops and temporary walls for special events. Conventions and so on. I come out of the union hiring hall. They call us out when they need something built. But I have worked there and most other hotels in town"

"What do you do at the Regents Hotel that caused you to get such a large amount of cash? I know the hotel didn't pay you, right? "

"I was hired to build a giant backdrop for the stage. It was supposed to look like a giant checkerboard. They hung big chess pieces on it, on hooks so they could move them around."

"You got a lot of money for building that backdrop?"

"No I was paid to do a special thing for one of the guys in one of the events"

"What kind of event and what did you do for him?"

"There was some type tournament or something. One of the players told me he is really superstitious and had a special checkerboard he wanted to use and…well the tournament requires them to use the provided board. So he asked me if I would replace the regular board with his special board just before the semi final match. And he gave me ten grand. CASH! So yeah man I did it. Wouldn't you? I mean somebody offers you ten thousand dollars to swap out the board for his good luck board"

"Are you telling me that the chess board was changed out by you just before the finals round began?"

"Yeah! The man said he had the lucky chessboard and he always won when he used it but I had to do it when no one was around to see me, so I did it after I finished the last backdrop. I brought it to the room inside by tool box. I still have the old one in my cabinet. I could trade it back out if I need to, but I already spent the money he gave me"

"Bobby! That was not a good luck chess board. In fact it is anything but a good luck board. Both players and one other person died along with dozens injured when the bomb inside the board .exploded. So Bobby, Why did you do it? Why did you kill these people?

"BOMB? What Bomb? The man told me it was his lucky board. Just ask him. He will tell you that he paid me to trade it out"

Bobby the players were killed by the blast. I can't ask him anything" Beckett tells the suspect "He's Dead!"

"No he is alive, I saw him outside the bar just before I went in on Tuesday. He was with the really pretty woman, they were kind of linked up. You know wrapped around each other and they walking in the front of the Four Seasons hotel like they were heading there for…you know…the evening"

Beckett and Castle look at each other "What did this woman look like? Can you describe her, or both of them?" Castle asks

"Sure, uh she Hot! I mean really good looking. She was probably late twenties, about five foot two, jet black hair, dark complexion, slender build"

Beckett gets a strange look on her face

"Bobby, if I show you a picture do you think you could identify her?" Beckett asks the suspect

"Sure. I mean I don't think I will ever forget her. I can identify her if I saw her again" Bobby responds

"Wait, I will be right back" Beckett stands and rushes out of the interview room. She almost runs over Ryan and Esposito as they exit the viewing room and all three are headed toward their desks and the murder board.

"Beckett, you don't think she is involved, do you?" Esposito asks as the three approach the photos file on Kate's desk.

She grabs the file and as rushes back to the interrogation. "It sure looks that way" Beckett answers

Back inside, Beckett takes a photograph from her file and lays it down in front of Bobby Pearson

"Do you recognize this woman?" She questions

"Yes. That's her" Pearson answers

Beckett takes another photograph from the file and places it in front of her suspect "Do you recognize this man?"

"Yeah! That 's the man who paid me to replace the checker board and the guy I saw earlier tonight with this woman" and he points to the first picture. "He's the man who gave me ten grand to change the boards out. He said it was his good luck board"

Kate looks at her partner and now new boyfriend and she smiles as she turns the photographs to face Castle. He looks down to the table to see the photographs of Margaret Matheson the widow of the English player that was killed and the unknown man who also left just before the bomb blast.

"It was not terrorist bombing! It was just a plain old lover's triangle murder"