It is a beautiful day in New York when things start to get really busy Mac is busy looking at the body of a woman who for some reason her face is covered in packing tape and has all sorts of marks around her body and something odd around her neck what is around her neck is a lock. Two people are writing on top of a car as it's moving it suddenly stops and one person falls off of it causing himself a lot of injury.
Minutes later someone is screaming that they're trying to kill him Mac asks the person if they know anything about the victim but before he can answer he collapses Mac asks for doctor Hawkes assistants.
Hawkes is at the hospital with a doctor treating the victim that fell off the car his status is rather grim and he is showing signs of organ failure. There is a long line at the hospital of people waiting to be treated or various other things. A brother of the victim or a friend of the victim is dying to know how his friend will be. Hawkes tells him that he is under the doctors care at the moment and isn't sure how his friend will turn out. His stomach contents are being sent to the lab so he can tell a little more about what happened to his brother.
Hawkes tells the victim's brother that he said someone was trying to kill him and if he mentioned anybody who would want to kill him. The victim's brother tells Hawks he didn't say anything and wonders if his brother will be OK.
Back at the lab Sid is busy examining the victim covered in packing tape and will soon find a startling discovery about the victim that will go as far back as 2002. Stella is busy examining the lock that was around the woman's neck. The lock has the words club random.
We find Stella and Flack at the place where the parties were held. The woman they've come to the interview is shocked that they're not here to join the party. Stella wants to know when the last one and was and who it belongs to.
The victim that had packing tape over her face was named Emma Pierce she attended the lock and key party to have some fun but they don't keep track of who their keys are given out to. Flack decides to confiscate the box of the keys.
Back at the lab Danny comes in with new information on Scott Colson who was into more than just two drugs and had along with sheet to prove it. Lindsay goes over the evidence she found on the clothes that Hawkes bought from a hospital. All Lindsay could find was a dollar bill and some hairs. Danny decides to go over to the place where Scott worked. Lindsay analyzed the stomach contents and found beats and something else in the stomach no poison was detected and she was still waiting for the results on that.
Danny goes to talk to Yuri Sokov who spent time with Scott Colson in prison in 2002. Danny believes he was the person that poisoned the food. First he claims not to remember Scott. Danny then threatens him if he doesn't cooperate with police.
Stella is busy analyzing the fingerprints found on the lock just as Detective Flack comes in wanting to know what she found. Detective Flack tells Stella that the cell phone is enabled with GPS but the signal is weak and he tells her that he will have the phone company search for someone who found the lock.
Justin Parks found her and took her to the party but later she tells him she's about to get sick he puts her in the cab to go somewhere. Stella wants to know if there was any chemistry between the two after they left the party and apparently there wasn't any. After he left the party he went home in ayellow taxi cab. Stella gets angry that he didn't bother to go home with her and make sure she was all right. "What a gentleman you are" Stella says rather angry. Justin didn't seem to care too much either way.
Sid begins removing the tape from the victim's face justice Mac comes in having received a note from the medical examiner. Mac is told that Sid found something disturbing after the tape was removed on the tape is a mark of the killer Mac arrested five years ago but unfortunately is out again due to a technicality. After Mac arrested Detective Dean Truby - the cop to whom Clay Dobson had confessed to murder - Dobson's conviction was overturned.
Mac carefully takes a look at the mark on the tape and tells the medical examiner he seen it before the medical examiner wonders if it's a possible copycat Mac issuers him that there is one person that could kill the victim. Clay Dobson.
Detective Flack comes in rather upset at Mac because Clay Dobson has killed another woman but Flack wonders why it doesn't bother Detective Taylor even a little bit. Mac tells the detectives to let him take the hit because he did the right thing by giving Mac his notebook in the episode entitled Consequences.
Detective Taylor still feels right in arresting Truby he was a dirty cop. Mack states to the detective his judgment has never been clouded. But is it possible that this time detective Taylor could be the dirty cop?
Flack asks Mac what he intends to do about Clay Dobson. Mac says he will be put him in jail for good this time. But because of the technicality and the possibly of arresting Clay Dobson things only begin to look bad for the detective.
After the break Mac decides it's to go see Clay Dobson and in his words rattle his cage. Clay Dobson would cut off his victim's eye lids with a modeling knife So that the cuts would be precise. Mac asks clay Dobson if he cut off his victim's eye lids as a way of control so they couldn't fight back or see who was cutting them.
Clay Dobson tells Mac that that is just "Ooh. That's just plain ghoulish". Mac also tells Clay that he's being watched. Mack leaves.
Lindsay calls Sheldon and tells him the results of the stomach contents. She says the poison wasn't found in the stomach but in his blood and Sheldon will look for an opening in the skin was to have been the place where the poison got in the blood. The Ricin was put in the pellet and then shot in his leg. Ricin affects the liver, spleen and kidneys and within two days the victim in dead.
Ricin is five times more deadly than cyanide to be able to get it isn't easy all you need is an Internet connection and a lot of money. Sheldon demonstrates how the ricin could've gotten in the victims leg by making a pellet and filling it with a deadly poison and using an air gun.
Danny and Sheldon head out to the park that was about to be sold for condos by his brother but apparently his brother didn't have any say in the matter either. The bearded lady tells and Danny and Sheldon that she was first hired when the park opened by Scott's father. Danny and Sheldon later decide to go see if they can talk to Jesse his brother was still at the hospital.
Mac is at his office answering the telephone. Stella comes back with blood spots found on the victim's arm they belong to a girl named Katie Lawrence who could still be alive. One thing puzzles Mac though blood transfers when it is wet so the transfer could've happened last night. Mac polls three folders and lines them up so Stella can get a good look at all three girls. They all look similar to Emma. Mack says serial killers have a type. Mac now believes that clay Dobson is the guy because Emma is dead as is Laruen Henning who Clay went to prison for killing five years ago. Mac believes this is no coincidence.
Stella interviews Katie's mother who knows for certain that her daughter is alive although the Stella can't determine that for sure at the moment the mother however is determined to find her daughter alive. Stella and the mother hold hands to give each other confidence.
Meanwhile inspector Gerrard shows up at Mac's office determined to know why he talked to Clay Dobson. Mac tells him Clay is the guy because of the signature found on the victims. The inspector feels Mac went after Clay Dobson because of the guilt of his release and perhaps his judgment is somewhat impaired. Mac firmly believes he has the right guy. The inspector hands Mac a folder inside that folder is the evidence from the blanket that was found earlier in the elevator. The suspect named in that folder is Martin bogs. Mac is told to go after him and take the surveillance off Clay Dobson. Mac refuses to follow orders.
Stella is about to undergo a PVR test this test will determine whether Stella is either HIV negative or positive. The PVR test is a faster result than waiting ten weeks to find out the result.
Adam tells Stella he will do the preparation and blood work results himself and she will be the first to know. Stella notices something on the screen Adam tells her that that is a specific kind of algae that was found on the victim's feet.
Mac comes in to the lab angry and shaking a folder at Adam and Stella. Mac is upset that he wasn't called right away with those results from Adam. He is angry that he had to get them from the inspector. Stella angrily shuts back that the inspector was a deputy inspector. Adam tells Mac that the inspector requested to see those results first and Adam was busy doing something for Stella. Mac tells them both he doesn't care what the title of the inspector's job is just that he gets the results as soon as they get it because there's a lot of information going in and out of the lab and he has to be on top of it. Stella tells Mac anybody would have done the same thing.
In New York Danny plays the game called snatch the bill in order to get kids to help them find information about Scott Colson. The kids tell Danny and Sheldon they saw Scott all the time. Suddenly they hear an air gun going off and they go to a booth where a young lady charges a dollar for some for several shots. The gun is then taken apart leaving the girls shocked and they find the pellet inside the gun which they believe was used to shoot Jesse.
Mac interviews Martin Boggs who claims he has nothing to do with what happened to those three women. He tells Mac that sometimes he moves single women and gets lucky the only person who can back him up is his wife. This time Mac was able to prove the inspector wrong who has been listening to the questioning.
Danny interrogates the young lady who had the gun at first she didn't tell Danny that she had a help until Jesse told her she could get 13 million dollars Danny tells her that if she doesn't tell the full story she could get 25 years in jail and be eligible for Medicare when she gets out.
The young lady also didn't know that Ricin was in the pellet she had in the gun when she ran into Jesse. Scott planned to kill his brother. Adam tells Stella her test results. She is HIV negetative. Adam feels bad for not telling Mac about the blood results Stella feels like she can dream again.
Mac Stella and Adam are all sitting in front of the computer that where Detective Flack was able to track a signal from Emma's cell phone. Mack asks that the five mile radius be checked to see if Martin Boggs moved any single women. They find out that within that five mile radius is a lot of apartment buildings. Adam then suggests that his uncle worked Weddington Hotel where lives seals were sometimes kept and crustacean shells were also found there.
Mac says Emma Pierce had mold under her finger nails he suggests they start with the basement as they begin to head down to the basement they notice a blanket missing from the elevator. Mack determines that that must have been the blanket they wrapped Emma in.
They continue to searching the basement they find magazines that are five years old and they also found a bed where the latest victim may have slept in leading them closer Katie Lawrence.
When they Katie she is bruised and scared she'd screams "Clay is coming back!" "Clay is coming back!" Then Mac realizes she means clay Dobson he's coming back. He immediately sets off to find Cay Dobson and arrest him. Flack follows close behind.
Lauren Henning was trapped in the basement five years ago. Stella continues telling Katie everything will be OK. Mac is back at Clay Dobson's place and sees him and a woman talking. Mack requests that Dobson take HIS hands off the lady and show Mac his hands. Clay makes a run for it out of a window that led into another man's apartment. The man in the apartment has no clue as to what's going on. Mac enters seconds later saying he's police and he runs through the apartment. Clay runs up a long flight of stairs to the roof of the apartment.
By this time the backup that Flack requested that still has not arrived and gets out of the car to tell all units that a police officer is in pursuit of clay Dobson.
Mac and Clay are on the roof together he tells clay to drop to his knees. Clay Dobson tells Mac that he was right about his victim's eyes he wanted them to look at him and be the last thing they would ever see. Mac replies shut up. Clay then asks Mac what he's going to do now is he going to shoot Clay? Clay tells Mac he has no gun Mac puts his gun in the holster.
Now that backup has arrived Flack begins to give orders telling two men to go around the front and two men to cover the street but before that can even happen clay Dobson falls directly on the police car cracking the windshield the police officer says "He's cuffed!" he's a cop and notices Mac still standing on the roof looking down. What really happened on the roof did he push clay Dobson?