Outside a sulfur springs, three kids park a jeep, load up on some beer, and then prepare to go skinny-dipping, the girl in the group, Lexie, expressing second thoughts about getting into the sulfur-smelling water. The two boys eventually convince her to get in and then she slaps one, believing that he made an advance on her. He denies it, then she turns to her other partner, believing that he touched her as well. When he denies it, a body floats to the surface of the water and Lexie breaks into hysterical screams.
The next morning, Jim, Ray, and other CSIs show up to investigate the body. Jim comments that body dumping in lakes of water is not a new form of disposal. Ray finds an L-shaped mark on the victim, consistent with trauma from a pistol-butt. CSIs are also able to confirm that the time of death was before the man hit the water or shortly after. They also find that the man's shirt is torn and that the estimated post-mortem interval is four to six hours. Ray says that their primary focus should be to find out what the man was doing, and whom the man was with.
After Ray takes a pool sample, Nick shows him a motor oil deposit that he found on the soil. The color indicates that it has been in a car for a long while. Ray ponders if that was how the man got out to the pool. Dr. Robins investigates the body with Catherine's help and, after asking her advice on what to buy his wife for her 50th birthday, comments that the L-shaped wound was not the cause of death. However, the man was suffering from pre-cancerous legions in the brain and liver, destroyed intestines, and other problems. But the man was not near the age during which it would be logical for these problems to occur. Catherine fingerprints the victim and then asks what killed the man. Dr. Robins tells her that the cause of death was drowning. He is able to remove a sample of the water that killed the man and collect it in a syringe. The sample of the water that Ray took, however, does not match the sample of the water that killed the victim, meaning that he was not killed by drowning in the sulfur water. Catherine analyzes he fingerprints that were taken and finds them to be a positive match to a Mr. Walter Burns. Burns was in the system for petty assault 25 years prior, however he had not been in recent trouble. He owned a house in Cable Springs and has a pickup truck, but the pickup is not at the house and Burns has no next of kin anywhere near him. He does not have many friends, save for Rosalind Johnson, the editor of the Cable Springs newspaper, who had called Burns twelve times before he died. Ray and Jim interrogate Johnson for information concerning the case, but she pleads her First Amendment rights and tells them nothing concerning why she was in constant contact with Walter, save for the fact that his health was of concern to her most recent story and that his wife was sick as well. A techie named Archie calls Nick and Greg in to show them an SUV that was recovered in town with blood on it. The owner, Richard Adams, had visited Walter's ranch half a dozen times in the past week. Greg analyzes the blood on the car and finds that it has saliva mixed with it. Nick finds an expended 9-mm shell inside the SUV. He reconstructs the scene. The shooter ordered the victim out of the car. Then they shot him near the throat, inducing a cough that ejected blood mixed with saliva. Archie tracks down where the SUV made its final stop, a hooker street. Nick and Detective Reed scope the place out, scaring a few hookers and clients along the way. While they walk, Reed tells Nick that she found out from a discussion with Adams' wife that the man was an engineer for a natural gas company called Conservo Solutions and that, on the night of his death, he called her and said that he was on his way home. Nick then finds a fresh blood spatter and he and Reed follow it. The trail ends with a skull fragment and 9-mm cartridge, indicative of the victim sustaining a gunshot wound to the head in addition to his previous chest wound. The two also find drag marks on the ground. They follow the marks and find Richard's body outside of a dumpster. Reed takes his cell phone and sees that the last call was placed to Rosalind Johnson. Nick comments that she must have been working on a powerful story in order for two dead bodies to be tied to it in twenty-four hours.
Nick has a meeting with Mrs. Adams to discuss her late husband. She tells him that Richard was, in his last days, very concerned about his safety and was sure that someone was following him. His job for Conservo Solutions was that of Safety inspector and he always checked out complaints from farms where the company drilled for natural gas. He had gone to Walter's property several times because Walter had filed several complaints. Richard had gotten several calls from Ms. Johnson concerning the possibility that Conservo Solutions was polluting the water deposits in areas where they drilled. Mrs. Adams, however, refuses to answer any of Nick's questions concerning what the complaints to the company were, saying that she would lose Richard's company benefits if she disclosed company business. Nick asks her if she was threatened and she responds in the affirmative, though not by someone at the company. She takes Nick outside and shows him a goat head, which someone left on her porch the day before her husband was killed. Ray and Dr. Robins analyze the goat head, which Ray believes was chopped off with a hatchet. Inspection reveals that the goat was dead before the head was taken off and that it had the same health defects and pre-cancerous legions in its brain and liver that Walter Burns did. Ray takes a sample to cultivate a culture and try to unravel what made the goat sick. Dr. Robins tells Ray that whoever sent the head did so as a sort of warning to Mrs. Adams. Greg analyzes the box and finds a bloody fingerprint. Archie analyzes Richard's phone and finds a picture of the same goat that wound up on the Adams' front porch (which Nick recognizes by the damaged left horn). Latitude and longitude tests reveal that the area the picture was taken was the ranch of a man named Bill Gibson and that Gibson lived down the road from Walter. Nick, Ray, and Detective Reed go to Gibson's ranch and start looking around. They hear a gunshot and follow the sound to Gibson, who is dumping the body of a recently killed goat. Gibson denies having killed Adams and/or having sent the goat head to Mrs. Adams. However, he remarks that Conservo paid him $50,000 for drilling rights on his property and that they were poisoning the water supply in his well as well as those of several of the other farmers n the area. They only covered one round of his wife's chemotherapy. Walter was his close friend and intended to find proof linking the company to the poisoning. However, he died before he could tell anyone anything. Despite Reed and Nick warning him, Gibson goes for a rifle. Ray tells him that they just want to understand what is going on and Gibson responds by throwing something into his water well that causes it to explode in a giant fireball.
The corner and other medical experts wheel away Gibson's body while Nick and Ray muse over why the water in a well would explode. Ray walks over to the faucet in Gibson's backyard and, as an experiment, puts fire in the water. The water sets aflame and the fire burns steadily. Ray then smells some of the water and hands it to Nick, stating that the fact that the water bubbles and its smell indicate that it has strong chemical compounds mixed into it. Ray invites Rosalind Johnson into his office and asks her about her story again. She tells him that the reason that Walter and Richard died was because they found out a year ago that Conservo Solutions was cutting corners and overlooking safety protocols in their drilling processes in Cable Springs and that the tainted water in was their fault. Richard asks her about her own health and she tells him that it will all be in her story but that she is missing one crucial piece of the puzzle. She tells Ray to look into what "fracking" is and then to give her a call. Dr. Robins goes over Gibson's body as Detective Hodges brings in the chemical reports on the water that was outside of Gibson's farm. Robins tells Hodges that the list of chemicals found in the water in Cable Springs have been shown to lead to a plethora of health conditions and cancers and that the water probably killed Burn's wife as well as Gibson's wife. Hodges also shows Robins the chemical report from the water that drowned Walter Burns. It seems that the water had the same chemicals in it that the other water did but at extremely high concentrations, consistent with the fact that Burns might have drowned in the source of all of the tainted water. Catherine tells her superior, Conrad, that they have to warn Cable Springs of the tainted water, but the man tells her that one polluted well is not ground for a warrant. Ray finishes his research on "fracking" and tells the two that it is a term for hydraulic fracturing. This is a process, in which natural gas is taken from shale rock below aquifers in the ground, releasing gas that is taken back up through the drilling instruments. The gas is then tested in an evaporating pool in order to determine if there is any excess gas in the water. If water protection programs are not followed, the gas and all other chemicals that are left underground can come up, along with water from the aquifer that is used, whenever a well is used or the water is extracted from the ground. Conrad tells Ray that he will call the Health Department while Ray investigates crimes. Ray points out that the crime is in the water. Gas companies have not had to file a report with any water protection agency since 2005, meaning that Conservo could be overlooking protocols and no one would know. He also states that the oil that Nick found at the scene contained soot, and titanium at 1400 ppms, a blend used in commercial fleets. Since Conservo Solutions owns the only commercial fleet in Cable Springs, both Walter and Bill signed over their mineral rights to Conservo, and Richard was a Conservo employee, this places Conservo solutions at the top of the suspect list. Conrad, however, is still not sure that this evidence is ground for a warrant. Ray tells Conrad that someone with a Conservo Solutions truck drowned Walter and that should be evidence enough. Catherine tells Conrad to procure the warrant.
Ray and Nick take the warrant and go to Conservo to investigate. Nick looks at all of the trucks and finds no leaks. He does, however, find a torn shirt piece, consistent with the torn part of Walter's shirt, on a Conservo fence right outside of the Conservo evaporating pool. Ray tells Nick that Gibson had told them that Walter was going to get evidence to prove Conservo's guilt before he died. He then surmises that Walter sneaked into Conservo at night to try to get a sample of the contaminated water from the evaporating pool that Conservo used. Someone found Walter snooping around and hit him with the gun. Walter fell in the pool and drowned. Then the killer took the body to the sulfur pool to dump it. Nick orders the foreman to call in all of his trucks and get license plates as well as drivers' names. Later, Greg calls in and informs the two that he has found the leaky truck (with blood spatters on the interior), the pistol that wounded Walter and killed Richard, and the driver. However, the driver will not be talking to anyone because he was just killed in a hit and run fatality.
Reed goes up and down the highway and finds no witnesses and no one who is willing to talk. Greg finds a valve on the truck loose by a quarter of an inch (which almost never happens without human intervention) and offers his theory. Someone set the trucker (Cody Trimble) up for a slow leak, then waited for him to get a flat tire and ran him over when he got out of the car to fix it, thus eliminating the final loose end that might possibly tie the murders back to Conservo Solutions. Nick and Ray go over all of the evidence on the gun (including blood spatter from Richard and hair from Walter) and are able to easily prove that Trimble was the killer. Later, Conservo lawyers place all of the blame on Trimble and call his death an accident. Conrad tells Jim and Catherine that, as far as they are concerned, the case is over. Catherine begs Conrad to keep the case going, saying that the families who Conservo destroyed deserve justice and that getting a sample of the fracking fluid in the Conservo evaporation pool is the only way to prove it. Conrad shrugs her off. Jim tells him that someone obviously paid Trimble to murder the whistle-blowers and then killed Trimble to tie up loose ends. Conrad still continues to refuse to reopen the investigation. However, he eventually relents and allows for further inspection when Catherine says that they still have to investigate the hit and run. Ray visits Rosalind and shows her that he has discovered what fracking is. Rosalind is impressed and Ray continues by telling her that Walter's attempt to get the fracking solution was her missing piece. She tells Ray that she tried to talk Walter out of his plan and that she had another source, Richard. She had worked on him for months and was finally going to get the documents that implicated Conservo from him, but he died before he could deliver. She says that she is also suffering from the pollution and hoped that she could expose Conservo before the end. However, now she intends to publish what she has. Ray tells her that Conservo will destroy her and her paper if she goes to print with a lack of evidence. She tells Ray that she is no longer afraid because she has nothing to lose. Ray offers her information on a clinic that a friend of his is starting up and tells her that there is a spot that is available for her. She takes the forms, thanks Ray, and leaves. Ray watches her go.