Malcolm continues to unravel as the mystery of the girl in the box comes to a head. As Nicholas Endicott's (guest star Dermot Mulroney) true colors continue to show, the Whitlys must decide to what lengths they are willing to go in order to take him down

When world-famous Europol profiler Simon Hoxley shows up in New York and claims that Major Crimes' current case is connected to the discovery of Endicott's body overseas, Bright fears he and Ainsley's secret is about to be exposed. Meanwhile, Martin gets to know Dr. Vivian Capshaw.

Martin is delighted when a murder at Claremont Psychiatric brings the NYPD into his territory, allowing him direct involvement with one of Malcolm's cases. While working the same job, Ainsley's suspicion grows when she feels Malcolm may be hiding something from her. All the while, Malcolm and Ainsley must dodge their mother, who's wondering why they got rid of her favorite rug.

The team investigates the murder of an architect who was tasked with renovating a supposedly haunted hotel.

Malcolm focuses on a case in which a famous plastic surgeon is murdered; Martin gets a new job working in the infirmary with Dr. Vivian Capshaw; Jessica is surprised to learn her younger sister is in town.

As Malcolm distances himself from Martin, Jessica does the opposite, diving head-first into the past for the sake of her tell-all book. Meanwhile, Martin is desperate to get in touch with his son ahead of his imminent plans, as Dr. Vivian Capshaw grows increasingly suspicious. Meanwhile, the NYPD investigates a crime of passion.

As the search intensifies for a serial killer on the run, so does Malcolm's tenacity, causing U.S. Marshal Emily Ruiz to kick him off the case. However, Malcolm doesn't back down that easily.

Bright's quest for answers about his childhood leads him to a junkyard, where he's bombarded with gunshots. Ainsley's exclusive interview with Martin takes an unexpected turn, forcing her to team up with Bright.

After a catastrophic turn of events, Malcolm and Ainsley are convinced there's more to Nicholas Endicott than meets the eye. Their only hope just might be an impromptu Whitly family reunion.

Despite Gil's fatherly concerns, Bright throws himself into a new case involving an escalating killer that has Edrisa's online vigilante group, known as the "Killabustas," trying to stop him. Meanwhile, Jessica realizes that she must dive deep into her past traumas in order to write a book and may need Gil's help to do it. Then, Martin's relationship with Dr. Capshaw intensifies.

After a terrifying incident at Claremont, Malcolm is in a race against time to track down multiple killers. The NYPD realizes someone close to home might be the key to finding them.

The search for a serial killer known as "The Woodsman" might help the NYPD find one of their own.

The FBI and NYPD band together to save Malcolm from the "Junkyard Killer," aka John Watkins, who reveals shocking details about his involvement in the camping trip memories that have been plaguing his psyche. Meanwhile, as Gil looks for answers from The Surgeon, Ainsley and Jessica search through their memories of the past, hoping to find some sort of clue as to where Malcolm could be hidden.

Jessica continues to search for more information on the "Girl in the Box," but is confronted by the "Carousel Killer," who has a very public vendetta against the Whitlys. While the NYPD investigates families tied to Martin's victims, it's ultimately up to Malcolm and Jessica to track down the tip-line caller, turned killer, who is blackmailing her. Meanwhile, Ainsley receives a big promotion at work, but quickly realizes she may never escape the high demand for serial killer reports.

When an up-and-coming ballet dancer is mysteriously poisoned, the NYPD dives deep into the rigorous world of dance. Meanwhile, Jessica reunites with an old friend, socialite Nicholas Endicott, and Bright and Eve turn to Martin for answers regarding the girl in the box.

Malcolm realizes the suspect in the "Junkyard Killer" case may have a connection to his father.

Malcolm and Ainsley both race to find the killer in the so-called "Debutante Slayings," but Ainsley's persistence has Malcolm worried about what her actual motive might be. While Martin is thrilled to see his daughter's passion in the field, Jessica suggests she and Ainsley take a vacation. Meanwhile, JT meets with his union rep to decide if he should file an official complaint against the cop who discriminated against him.

When a body is found professionally preserved and embalmed, the NYPD teams up with Edrisa to go undercover at a convention of funeral directors. While there, they discover their top suspects - morticians Tilda and Dev - who used to be in business with the victim. Then, enter the mind of a serial killer as Martin revisits his past through a series of hallucinations.

When a priest is found murdered in his place of worship, Bright grapples with its effect on his own trauma.

When the headmaster of Bright's alma mater is found murdered, he is forced to face a troubling secret from his past. Meanwhile, Jessica struggles with her decision to end things with Gil, Martin grows closer to Friar Pete and JT eagerly anticipates the birth of his baby.

When Bright uncovers a photo of himself and Martin from when he was a kid, he is forced to focus on the repressed memories from his childhood psyche. Jessica and Malcolm agree they must put a stop to Ainsley's idea.

Following a mysterious and catastrophic incident in the precinct, Bright faces an internal affairs review as Gil and the team worry about his mental health.

Malcolm takes a detour from his mandated vacation time when he finds out a killer on the loose is mimicking homicides from one his favorite children's books, "The Count of Monte Cristo." With added help from a very excited Martin Whitly, the NYPD trace the case back to a high society family planning one of the biggest weddings of the season, so Malcolm and Dani get dressed up to attend the event and track down their culprit.

When a motorcycle gang robbery turns into a murder, Malcolm and team are called to the scene to investigate. While he's working on a profile, he runs into an old friend from boarding school, licensed insurance investigator Vijay (guest star Dhruv Singh). Together they work to uncover the identity of the murderer and his accomplices who stole millions in watches. Meanwhile, Martin blackmails Jessica, exchanging his silence about who stabbed him for more quality time with his son.

Bright finds his personal life in disarray after his sister's shocking actions. Now, he has to "take care" of her and protect his mother, Jessica, from a secret that could tear the family apart all over again. To distract himself, Malcolm takes on a new case and must find the killer behind a recent beheading in the city... and the only person he can turn to for help with the case is his father. Meanwhile, Martin returns to Claremont to a surprise new roommate and JT faces discrimination while on the job.