A homicide detective teams with a man who takes on incredible but uncontrollable strength when enraged. In the series opener, the two meet for what they discover isn't the first time.

As Cat and Vincent hunt for a black market buyer searching for beasts, they have to protect an heiress whose identity was exposed. Cat and Vincent realize how much they have to lose if Vincent's true identity is revealed.

Vincent helps Cat investigate the suspicious death of a ballerina. Meanwhile, Tess makes a surprising discovery about the man she's dating.

Cat is placed on leave after interfering in a murder investigation. Meanwhile, J.T. fears that Vincent will become exposed.

While working to uncover who is after Vincent, Cat discovers she might be pregnant. A lead Vincent follows puts his life in jeopardy. Meanwhile, J.T. gets kidnapped in a case of mistaken identity.

With Vincent in hiding and Cat's job on the line, they must re-group about how to bring down the people hunting beasts. Vincent tries to infiltrate a private army, while Cat scrambles to obtain information and hopes that no one at work discovers her ulterior motives.

When Cat and Vincent make it their mission to capture Liam, they find information about a Patient X that they might be able to use to help them find him. Meanwhile, JT and Tess work to confirm that JT is serum free.

Vincent and Cat’s wedded bliss comes to a halt when they learn from J.T. that someone is trying to expose the identities of beasts. While on the hunt to find out who is behind the threat, Tess is reluctant to help since they are all trying to move forward with an attempt at normal lives.

While attempting to be normal newlyweds, Cat and Vincent grapple with how to overcome the danger lurking. They find themselves in the fight of their lives when their happiness becomes jeopardized.

Vincent and Cat fight to reclaim some normalcy to their lives, even as the threats of a beast bounty and a DHS manhunt loom. Meanwhile, Tess takes a huge risk by protecting Vincent from a nosy reporter.

Vincent is forced to undergo a series of tests orchestrated by the mystery buyer in order to keep from being exposed. Cat, JT and Heather work to exonerate Vincent.

When Vincent and Cat discover they lost control of their secret, they finally admit it might be time for life on the run. Vincent realizes he must face his past, while Cat worries about how much they have to lose.

Vincent is torn between his new feelings for Cat and his old memories with Alex (Bridget Regan). J.T. learns that Evan is planning to propose a task force to catch the beast and must figure out how to stop him. Meanwhile, Tess investigates the mysterious skydiving death of the wife of a billionaire adventurer, while Cat remains off duty until she recovers from being shot.

Cat and Vincent take Agent Knox's offer to extricate and try to lead normal lives -- but forces out of their control conspire to expose them and drag them back into the fray.

Vincent and Cat decide to elope in order to draw out a superhuman assassin chasing them. J.T. tries to find a lead on the experiments, and Heather tries to focus at her new job.

After a force more powerful than anything they have ever encountered ruined Cat and Vincent’s big day, Cat becomes convinced they are in over their heads and begins to doubt their ability to stop the threat, forcing Vincent, JT, Tess and Heather to band together in hopes of convincing Cat of her greater purpose.

Vincent and Cat realize they have to go into hiding now that someone is out to kill Vincent. Vincent wonders if Cat would have been better off without him and gets a glimpse into exactly what her life could have been.

Vincent goes undercover with a sexy operative, who Cat discovers is an assassin. Vincent has to play both sides, while Cat has to convince DHS she can still be trusted.

Vincent revives a 19-year old boy who was left for dead in a dumpster and rushes him to the E.R., where he remains in a coma. After Evan declares that the boy's x-rays reveal a history of bone fractures, Cat and Tess question the father, Zachary Holt, who worries that his son's ADHD and history of fighting and gambling might have gotten him mixed up with the wrong crowd. The detectives question Lois Whitworth, who owns the Westchester Polo Club where the boy worked. Lois is surprised to learn that her daughter, Clarissa has been dating this young man. Clarissa claims that she ended the relationship because he was involved in illegal activities, but Cat and Tess suspect that there's more to her story. Meanwhile, Silverfox and his Murifield agents track down Cat, and offer to tell her the truth about her mother in exchange for turning over Vincent, who they insist is a monster. Cat tells Vincent about her Silverfox encounter, and Vincent realizes that Cat might be afraid of him. JT wants them to flee, but Vincent refuses to leave Cat, instead offering to surrender to Silverfox in exchange for Cat's safety.

Cat confronts her birth father about the mysterious role he's played in her life, while Vincent has to neutralize a high-profile beast. In the process of doing so, Vincent finds himself rescuing Tori, a damsel in distress, who may be the key to completing his mission.

Vincent moves in with Cat which forces them both to address the rapid changes in their relationship while they investigate a shocking new lead in their hunt to track down who is behind the super-human experiments. JT tries to impress Tess’ brothers and discovers that there may be some side effects to the medicine he received from Agent Thomas. Meanwhile, Heather returns to town with a surprise announcement.

Cat and Vincent take their relationship to a couples counselor when Cat dives into her work and suspects a wealthy transplant recipient of being involved with the mysterious experiments on innocent people in the city.

In a surprising turn of events, Vincent agrees to help Liam on a mission to retrieve evidence that could expose them both. Meanwhile, a suspicious Cat discovers something about Liam's family history and must warn Vincent before it is too late.

Liam’s shocking history makes Cat delve deeper into the Ellingsworth family, where she learns of their tragic past. Vincent and Cat realize that they will need to use their secret weapon if they want to take Liam down. Meanwhile, JT has a theory about how to save himself but it involves none other than Liam.

Vincent is captured on a convenience store surveillance video while preventing a robbery, and Cat warns him to be extra careful when his photo appears in the newspaper. Cat and Tess investigate the disappearance of a woman named Amy (guest star Annie Murphy), who has gone missing after her fiancee, Dr. Michael Walters (guest star Jeremy Glazer), surprised his bride-to-be by placing their engagement announcement in the paper that morning. Evan runs Amy's fingerprints and discovers her true identity, while Cat wonders if her disappearance was intentional after Vincent mentions that he and JT have an escape plan to clear out of their loft without a trace in a matter of minutes. Later, Michael also goes missing and Joe learns that his team has been deceived. Meanwhile, Heather is planning a surprise birthday party for her sister, forcing Cat to postpone her birthday plans with Vincent. At the party, Cat and Evan share a surprising moment.