Brennan awakes in a car not realizing where she is. When she tries to exit she realizes that the car had been buried underground. She turns to find Hodgins in the back seat with broken legs. She realizes that they've been caught by the Grave Digger.
FLASHBACK 48 hours and Brennan and Booth arrive to a crime scene in the woods where a sheriff claims local kids found a flying saucer with aliens onboard. When Brennan gets a look she discerns that they are two young boys and the "flying saucer" is a beer vat sealed shut. Judging by their decomposition, she knows they've been dead for years.
At the lab with both bodies out for examination, Zack explains that one of the bodies has multiple broken bones while the other body has none. Also with the amount of blood found in the vat, he thinks that the boy with the injuries bled to death, while the other boy would have later suffocated. He also adds that they were twins. Booth enters with a photo of the boys, Matthew and Ryan Kent. They were abducted in 2001.
B&B sit with AUSA Kim Kurland and ex FBI agent Pete Sanders. They worked the Kent case in 2001. Since then Sanders has become a drunk, but Kurland has remained on the case. Sanders told the Kent parents not to pay the ransom, following FBI protocol, but the Grave Digger didn't budge. The Grave Digger has consistently been cooperative when he is paid on time and has never revealed the location of the buried hostages without being paid. Kurland tells B&B to talk to Thomas Vega, who wrote a book on the Grave Digger.
B&B sit with Vega and question him. Vega is joined by a journalist, Janine O' Connell, whom helped Vega write his books. They seem to admire and loath the Grave Digger all at once and it doesn't sit well with Booth.
In the lab, Zack finds burn marks on the neck of one of the boys, most likely from a stun gun, but the other boy with the broken bones does not have the same markings. Hodgins arrives with info that concludes that the boys were most likely in an indoor parking lot before they were kidnapped. Brennan tells both Zack and Hodgins to compare their findings with the files on past victims.
B&B sit with the father of the twins, James Kent. He's not thrilled to be working with the FBI again after their advice led to his boys' death. While cross referencing facts with Mr. Kent, Brennan gets a text message from Hodgins saying that the twins only had 12 hours of air while the Grave Digger gave Mr. Kent 24 hours to wire the money, which means the Grave Digger either was going to kill them anyway or he miscalculated his kidnapping and had to take both boys instead of one.
At the lab, Brennan and the squints examine the containers that the past victims were buried in and Hodgins inspects their clothes to find the same residue that would confirm that all of the victims were taken from indoor parking lots.
Around the Angelator, Angela shows B&B a scenario proving that the injuries to the one twin happened before he was put into the vat, but Brennan adds that the amount of blood on the floor couldn't have come from his skeletal injuries. Booth chimes in with his idea that the Grave Digger probably tried to kidnap just one of the twins and when the bother showed up and interfered, he was hit with a car a then kidnapped as well.
Brennan heads out to a martial arts class and while at her car is approached from behind and then falls unconscious. Hodgins comes out to find her, but is then hit by a car.
With Cam and Booth out to dinner, they talk about their relationship. Booth gets a call on his phone from the Grave Digger asking for 8 million dollars in exchange for Brennan and Hodgins location.
Booth is joined by AUSA Kurland, Vega, and O'Connell and they dicuss a plan for getting their friends back. Vega suggests that they do as the Grave Digger asks and O'Connell wonders why he's asking for so much money. Booth explains that Hodgins is the heir the Cantilever Group.
Now back with Brennan and Hodgins in the buried car where we left them in the teaser, Brennan dresses his wounds from the car accident and they try and piece together what's happened to them. Neither of them have memory what happened just before they woke up in the car. They calculate that they have only 10 hours of air left.
In the lab, Booth gathers the squints to fill them in. They head to the parking lot to scope out the area around Brennan's car. Cam spots a puddle of blood and they call for FBI to inspect the scene.
In the buried cart, Brennan takes inventory of what they have to survive: water, some pens, a laser pointer, a broken cell phone with extra batteries, and her latest novel. Hodgins also has a bottle of perfume that he purchased for Angela. Hodgins complains of leg pain and Brennan thinks he might have compartment syndrome and he could slip into shock and die.
In the lab, Cam presses Zack for info. Zack says that the stun gun search was a dead end, but he did find that the injured twin stabbed himself in the neck with a pen, killing himself. Cam thinks he did it to give his brother more air. Zack doesn't know why that matters and Cam tells him that it will matter when she tells their father.
In the buried car, Brennan has an idea of how Hodgins can avoid the compartment syndrome. She must make a long incision along his leg to relieve the pressure. The pain will be high and it could send him into shock, but he will surely go into shock if they don't do something. Before the incision, Brennan finds some kind of sticker in his leg, a clue. She then cuts in.
In the lab, Cam meets with Booth to find out that the Cantilever Group has a policy of never paying for ransom without a proof of life and Hodgins is the one who created the rule. They think that they must have been close to finding something on the Kent boys case and the Grave Digger wanted to take them off course.
In the buried car, Hodgins wakes up to Brennan's relief. She's hotwired her cell phone to the wires of the car horn. With a beep they might be able to send one text message before frying the phone, but first they need to figure out what message to send. Brennan opens the window to get some dirt and gives it the "the dirt man" himself to find out where they are. He finds coal in the dirt, which means they're in coal country, specifically Virginia. He uses the chemicals in the perfume to find out what kind of coal. He also looks at the piece of plastic found in his leg and concludes that it's most likely a bumper sticker, more specifically a toll road pass sticker. Hodgins now realizes that he was hit by a car. Brennan readies the phone to send their message. She honks and Hodgins sends it.
With Booth, when he gets the encoded text message. He runs to the lab to ask the squints if they can crack the code, but the 10 hours has passed and they assume that Brennan and Hodgins have run out of air. Booth won't settle for this.
In the buried car, Brennan has cut through the back seat into the truck for more air. She also cuts into the spare tire, but it's looking bleak. Hodgins looks at their supplies again and realizes that if he leaks the batteries and mixes them with the chemicals in the dirt, he can create oxygen, but not much.
At the lab, Booth is flying off the handle because the squints have given up, but he won't let that happen. He orders them to keep thinking of ways to locate them. Zack buckles down and solves the text message and they head out to find Brennan and Hodgins.
In the buried car, Brennan has rigged a last resort using the explosive charge of the airbag to blast the windshield out. If they are less then four feet below the surface this could get them to freedom, if not, the concussion will damage their brains.
Booth and the team arrive to where they think Brennan and Hodgins are buried. The area they need to search is a little greater than three football fields, but with help from the FBI they spread out. Just when people are starting to give up Booth spots a puff of dust shooting through the ground; the explosion from the airbags. He bolts over, starts digging, and everyone follows. Brennan and Hodgins are pulled to the surface, but the Grave Digger is still at lagre...