When teenagers who were reported missing are suspected of a series of mass murders in Chicago, the BAU investigates their whereabouts to find a motive for the crimes

A deadly face-off leads to a life-threatening moment; Catherine and Sam seek help for his parents.

Bill's latest discovery is put in jeopardy, even as trouble brews with the human aliens; Catherine must decide where her loyalties lie.

Threatened with expulsion, Yumyulack and Jesse continue to attend their empty high school after the school year ends. Unaware of the summer break, they believe they are being tested, and attempt to teach each other. They realize their mistake and wreak havoc on the school, and are bribed with straight As after discovering Principal Cooke and Mrs. Frankie having sex in the cafeteria. Korvo and Terry enroll in a junior college, but Terry shoots Korvo with a raygun that makes him dumber. Korvo joins Terry's hard-partying college experience, but accidentally causes the "ice lava" that powers their spaceship to flood the city, freezing everyone in its path.

Korvo tries to get the family involved in repairing the spaceship, but they attend a birthday party instead, where he is inspired to become a magician. Using his computer system Aisha, Korvo creates a technologically advanced magic act; he goes viral and prepares for a Las Vegas show, which will culminate in him leaping through a black hole. Korvo ignores his family's warning that jealous magicians plan to kill him; the family save him from being shot, but he dies when the black hole trick goes awry. The grieving family agree to repair the ship in Korvo's memory, and he reappears, having faked his death to bring them closer together. Yumyulack adds a woman named Cherie to his shrunken collection.

Inside the Wall, Tim – imprisoned and tortured on the Duke's orders – is convinced by his cellmate Jean-Pierre to write letters calling for revolution. They are rescued by Cherie and her fellow rebels, and prepare to overthrow the Duke. Tim and Cherie spend a passionate night together, and copies of Tim's letters spread throughout the Wall, drawing people to their cause; Cherie urges Tim to lead them. As the Duke addresses a congregation, his sheriff spots Tim in the crowd and attacks, killing Jean-Pierre. Tim unites the oppressed inhabitants of the Wall in an open rebellion. The Duke floods the lower levels, drowning countless people; a farmer named Steven is unable to save his beloved mouse, Molly.

When the Pupa turns orange, Korvo realizes he left important Pupa information in his wallet on Shlorp. He and Terry travel back in time to the day they evacuated Shlorp, and knock Korvo's wallet into their spaceship. Returning to the present, they realize the Pupa merely ate something orange, but the time stream has been altered and they now live with Vanbo, an obnoxious Shlorpian. Returning to the past to set things right, Korvo and Terry learn they did not want each other as evacuation partners, but reconcile and beat up Vanbo. Yumyulack discovers Jesse has simulated a nicer version of himself in the "Pretend-O-Deck". His simulated self teaches him to be a better brother to Jesse, but one Yumyulack kills the other.

A deadly face-off leads to a life-threatening moment; Catherine and Sam seek help for his parents.

Bill's latest discovery is put in jeopardy, even as trouble brews with the human aliens; Catherine must decide where her loyalties lie.

When a toddler falls down a pipe and becomes trapped, the 118 must rely on more than their skills to rescue him; old wounds are opened when members of the 118 race to the aid of a man dealing with a divorce.

When Athena is assigned a rookie to mentor, she begins to question her own abilities.

Athena and Hen face increasing dangers in space as friends both near and far try to get them home safely; the 118 continues to help victims of the geostorm and falling debris.

When a sniper strikes Dallas, the BAU investigates whether the upcoming anniversary of the Kennedy assassination is a motivating factor or if something else is driving the UnSub.

The BAU meets their new section chief, Mateo Cruz, who, unbeknownst to them, shares a long work history with JJ.

When a body is found in the theater of Martha's latest show, Castle and Beckett's investigation leads them into the unexpectedly dangerous world of competitive a capella.

Castle finally gets his day in court when he takes the stand as the key witness to a murder from five months ago. But when new information suddenly arises, he and Beckett must race against the clock to prevent a miscarriage of justice.

The son of a Russian diplomat is murdered; during the investigation, Castle entertains a jovial Russian security guard, who turns out to be more involved in the case than expected.

As Hotch fights for his life due to complications from his stabbing at the hands of George Foyet, a.k.a. “The Reaper,” he experiences visions of his late wife, Haley, and his nemesis, Foyet.

When the BAU investigates victims of possible ritualistic murders in Utah, clues lead them to believe that the UnSub they are looking for might have a fascination with the Salem Witch Trials.

The team take a look into the death of a mini-golf superstar. Brennan is concerned about her dad.

Booth and Brennan work cover as they become involved in the world of underground poker.

The son of a Russian diplomat is murdered; during the investigation, Castle entertains a jovial Russian security guard, who turns out to be more involved in the case than expected.

Beckett and the 12th Precinct look into the murder of an English as a Second Langue student. But when the victim's class won't talk to the police, Castle goes undercover as a French Canadian immigrant and learns that the victim was more than he seemed.

After discovering the body of a missing girl 13 years later, Will and Faith reopen the case leading to Will experiencing frequent flashbacks as they uncover the truth; Angie and Ormewood investigate the death of a veteran.

To deepen his connection with his late mother, Will joins Antonio in Puerto Rico; upon his return, he is quickly brought onto a case involving his uncle's old friend; Faith and Ormewood investigate the mysterious death of a sex offender.

In order to hunt down the brutal murderer of a grifting seducer, Castle and Beckett must investigate New York's elite. Meanwhile, Castle plans to surprise Beckett on their one-year wedding anniversary.

Castle and Beckett investigate the murder of a cruise ship entertainer, only to find themselves trapped at sea with the killer.

Colter is hired to find a mother in Ohio who went missing after tucking her son in for the night.

The BAU heads to Bethesda, Md., to investigate four murders in the span of three days along the eastern seaboard. The crimes become personal for Alvez, when the team discovers there are ties to his time spent five years ago working alongside the DEA and the Mexican police force in pursuit of the most notorious hitman in Mexico. Also, Alvez and his girlfriend, Lisa, decide to move in together.

When a sniper strikes Dallas, the BAU investigates whether the upcoming anniversary of the Kennedy assassination is a motivating factor or if something else is driving the UnSub.

The BAU meets their new section chief, Mateo Cruz, who, unbeknownst to them, shares a long work history with JJ.

The team take a look into the death of a mini-golf superstar. Brennan is concerned about her dad.

Booth and Brennan work cover as they become involved in the world of underground poker.

When two off-duty cops are wounded, the GBI must track down Special Agent Will Trent, who recently fled town to help solve the case; as the investigation unfolds, Will is drawn into his past to clear a friend's name amid rivalries and corruption.

The remains of a popular TV celebrity chef are discovered at a local park, and the Jeffersonian team must search for clues in local restaurants that he had been reviewing. When evidence points to the Royal Diner, Brennan and Booth's favorite eatery, the two must risk their status as favored patrons by questioning the staff. Meanwhile, Hodgins sells his new invention for millions and Brennan creates an anatomically correct song to help Christine learn about the bones in the human body

Things get messy for the 118 following a massive pipe explosion; Athena investigates the brutal beating of a man found behind a grocery store.