The 126 race to save a man crushed under a vending machine. While struggling to handle his aggressive foster horse, Owen finally faces the truth of his brother’s death. As Mateo and Nancy scramble to delete a nude photo of her accidentally sent to the 126, Tommy is concerned that Nancy may be facing a possible health scare.

London, four months after the attack. The survivors organize the Resistance. Bill continues his research on aliens and understands that their DNA is human but that their organs are degenerating. In France, a severely wounded dissident alien reaches the Observatory

At the Observatory, Mokrani and Catherine clash over the fate to be reserved for Micah, whom Catherine considers to be a major source of information. Micah reveals to Catherine that she has to find Bill Ward. The latter, for his part, tries to find out more about Emily, still assailed by visions of Adina, the leader of the aliens urging him to kill Bill.

Lou, feeling like M.O.D.O.K. is stifling his individuality ahead of his bar mitzvah, jumps into M.O.D.O.K.’s portal to Asgard. There, Lou is taken by a tribe of goblins known as Kobolds, but wins them over with his magic tricks and becomes their leader. He refuses to go back home with his dad, so M.O.D.O.K. takes control of an army of Asgardian warriors and wages war against his son. Eventually, M.O.D.O.K. and Lou strike a deal and use Lou's magic tricks to pacify the Kobolds. Meanwhile, the Super Adaptoid agrees to help young M.O.D.O.K.

With Richard's help, Catherine discovers she can travel to another world; a new revelation puts Martha's loyalties to the test; Zoe breaks Bill out of prison.

Tom grapples with a betrayal and encounters a familiar face; Catherine looks for a solution to the dangers of the black hole.

The BAU heads to Indianapolis, Indiana where a bomb has just exploded at a popular chain coffee house, killing several. The police believe this bomb is related to a bombing one week earlier at a school.

When a coded document hidden by a murdered bail bondsman gets Castle's imagination running wild, Beckett must steer the case back to the violent felons who populated their victim's world.

Peter Folkmore was an abused child and is an abuser as an adult. He captures women and abuses them for not reciting the exact instruction Peter gives them.

Castle and Beckett look into the murder of a young mathematician gunned down with a 200-year-old bullet, sparking some wild theories by Castle about a time-travelling killer.

When body parts of a Coast Guard Reservist are found in the belly of a poached wild boar, Longworth hunts the killer into the depths of the Glades.

The 126 race into action when a horse barrels into a brewery with an unconscious rider on its back and then to a bus full of tourists all experiencing seizures. Judd introduces Owen to Wyatt’s mother Marlene. Carlos and T.K. start couples counseling, when Carlos investigation into his father’s murder becomes all-consuming.

Another layer is added to the mystery of Booth's whereabouts and the state of his physical condition when the team discovers that FBI Agent Miller (guest star Kim Raver) has not been entirely truthful with the FBI and the Jeffersonian, keeping vital information from them that could lead them to Booth. Meanwhile, the Jeffersonian gets a surprise visitor, FBI digital forensic scientist Dr. Benjamin Metzger (guest star Josh Casaubon), who works with Angela to try to decode the information the team has been able to uncover regarding Booth's location and the circumstances surrounding his disappearance. Also, Arastoo makes a major decision that affects his and Cam's personal and professional relationship.

The BAU heads to Indianapolis, Indiana where a bomb has just exploded at a popular chain coffee house, killing several. The police believe this bomb is related to a bombing one week earlier at a school.

Peter Folkmore was an abused child and is an abuser as an adult. He captures women and abuses them for not reciting the exact instruction Peter gives them.

Dr. Daniel Harrow investigates the apparent suicide of a young woman whose grieving father suspects she was murdered.

When body parts of a Coast Guard Reservist are found in the belly of a poached wild boar, Longworth hunts the killer into the depths of the Glades.

Mysteries abound when pallbearers at a funeral lose control of a surprisingly heavy casket only to have a second unknown woman tumble out along with the original deceased.

On Brennan and Booth's first official day back at their respective positions at the Jeffersonian and the FBI, things get exciting when remains are found at a fish farm under suspicious conditions, prompting them to investigate. After it's discovered that someone harvested several of the victim's internal organs before he was dumped in the water, Angela tracks down the seller and buyer of the organs to try to uncover important details in the case. Meanwhile, Booth readjusts to his position back at the FBI and discovers Aubrey has taken over his old office; Hodgins pushes Angela to showcase her photography work; and Cam struggles with her decision to choose work over her relationship with Arastoo.

When a beautiful woman is found dead in an alley, all clues point to her being a victim of the notorious Triple Killer. The Triple Killer, or 3XK, terrorized New York City four years ago, then mysteriously disappeared. Now he's back.

TK gets a huge surprise on his 30th birthday when his stepdad Enzo (guest star Henry Ian Cusick) arrives in Austin along with TK’s young half-brother Jonah; Owen’s resentment of Enzo turns physical; Tommy is determined to push through her latest crisis; Wyatt attempts to talk-down a suicidal caller and the 126 must perform a dangerous surgery in the field after a man is impaled in a tree.

When two guards at a privatized maximum security prison in Texas are murdered, the BAU suspects that more than one UnSub within the prison could be at work.

The BAU is called to Wisconsin in search of a serial killer, and the team looks for a connection among the victims for clues to the UnSub. Also, Kate has trouble dealing with her niece, Meg, when she begins acting out.

While stalling the river bones investigation, Harrow digs into the case of a woman murdered with a crossbow, coming dangerously close to a thrill-kill murderer.

When Colter suddenly disappears during his search for a missing father, Reenie recruits his brother, Russell (Jensen Ackles), for help.

When body parts of a Coast Guard Reservist are found in the belly of a poached wild boar, Longworth hunts the killer into the depths of the Glades.

Mysteries abound when pallbearers at a funeral lose control of a surprisingly heavy casket only to have a second unknown woman tumble out along with the original deceased.

While stalling the river bones investigation, Harrow digs into the case of a woman murdered with a crossbow, coming dangerously close to a thrill-kill murderer.

When remains of real estate agent Justin Ross are found in the forest and appear to have been destroyed by coyote-wolf hybrids, Brennan enlists the help of fellow brilliant forensic anthropologist Dr. Beth Mayer (guest star Betty White) to assist in the investigation. In addition to her professional achievements, Mayer is surprisingly knowledgeable about the world of fantasy football, a key link to Ross' past and one that could provide vital information in finding his killer. As Booth and Aubrey dig into Ross' fantasy football league history, they discover he was actively involved in a Twitter feud with NFL star Lou Divers (guest star Ronde Barber), and was also owed a large sum of money from the league's commissioner, making each of them suspects. Meanwhile, Brennan resists feeling competitive as Mayer impresses the team with her expertise and decades of accomplishments.

When the wife of an increasingly prominent Congressman disappears, the BAU investigate and come to consider his adversaries and political enemies as potential suspects of the abduction, or possibly murder.

A gang killing leads Carlos to new information on his father’s murder. TK contemplates a major life decision as Owen is determined to get Austin’s first responders’ health care coverages increased.

While investigating the murder of a NYC subway worker found shot to death in Central Park, Castle and Beckett unexpectedly uncover the shocking and violent abduction of a young boy.

When an innocent family of four is abducted while vacationing in Barbados, Hotch and Cruz enlist the assistance of the FBI's most elite team in handling international cases. They realize that this situation closely resembles a case that the BAU once handled in Florida.