Vincent takes Alex to the ice skating rink they used to frequent when they were young and Vincent finds the lock on the door is still broken after all this time. Their session is interrupted by a Police officer who asks for their names and Alex volunteers hers but Vincent refuses until he can make a phone call. He calls Cat and she has to lie to cover for him. Along with supplies stolen from the hospital she works at Alex takes Vincent to a shop which hides a volunteer free medical drop-in center and suggests Vincent could return to practicing medicine. Evan contacts ...
Alex takes Vincent to her secluded cabin in the woods. JT attempts to convince Evan not to attend a seminar to present findings on cross-species DNA research. Alex's apartment is due to be raided by Cat's department as part of investigation into stolen medical supplies. Cat goes in before raid and removes photos and other evidence that Vincent had ever been there. Muirfield track Vincent to cabin and set a trap which Vincent senses.
Cat told Vincent that she wouldn't be second choice after Alex and so on St.Valentine's day Vincent is desperate to win Cat over. JT offers advice on how to woo Cat, (taken from the internet and which he is using for his own girlfriend). Vincent sends Cat cut flowers which she gives to Tess,then chocolates followed by street dancers who surround Cat as he watches her online, none of which impresses Cat. Meanwhile Cat contacts Alex and warns her that she is now on Muirfields radar and they will use her to get to Vincent so she must disappear. Evan is suspicious of ...
After a dinner where Cat introduces Vincent to Heather ends badly, Heather enlists Tess to stage an intervention with Cat. Evan receives an interesting proposition that could change the course of his cross species investigation and at an event to honor Joe, Heather goes missing and Vincent is forced to make a tough decision that saves her life.
There's a manhunt for the vigilante because the police believe he killed Bishop's brother and nearly killed Catherine's sister. Catherine knows the circumstances of what happened. So she again tries to help Vincent. So she tries to find the witness who knows what happened. A new A.D.A. shows up and questions them about why they're unable to find the vigilante.
Cat and Vincent spend the night together. Cat is called to another vigilante crime scene but when she tries to convince Joe this is not the work of the vigilante he ignores her. Muirfield contact Evan, expecting him to sabotage the forensic evidence if necessary to keep the task force from finding the vigilante so they can get to him first. Tess is angry with Joe for sidelining her from field-work and sending her instead to interview the victims of attacks that the vigilante protected. Cat and Vincent rig the lab to blow when the task force arrive but Muirfield get ...
Cat rushes to Vincent's aid, trying to persuade Tess that he is not the danger Tess thinks he is. JT ends the standoff by firing a tranquilizer dart. Cat has to leave Vincent to guard Tess to stop her from revealing his whereabouts and he attempts to convince her not to turn him in for Cat's sake. Cat goes to Tess's apartment to find files that would prove he only killed those committing criminal acts. Vincent lets Tess go, although she remains unconvinced and goes straight to A.D.A. who assigns two cops to go with Tess into the underground tunnels to catch Vincent. ...
Evan, in a misguided effort to protect Cat, gets himself jailed so she will be visiting him while Muirfield hunt for Vincent in the tunnels. Muirfield arrange for Evan to be taken to the same facility where they are now holding Vincent. Meanwhile Cat discovers where Vincent's being held with JT's help, and mounts her rescue plan. Evan overhears Muifields plans for Vincent and realises he has been duped. Cat releases Vincent and Evan apologises for betraying him, but during their escape Evan gets fatally wounded and sacrifices himself in more ways than one.
Three months after Vincent Keller was abducted by Muirfield, Detective Catherine Chandler is reunited with him - but not in the way she planned. He's changed: his scar has disappeared, his memory has been wiped clean and he returns as a supercharged beast on a mysterious mission.
After getting stonewalled by Cat in his quest to track down a suspected beast, Gabe enlists Vincent's help, but Vincent quickly takes matters into his own hands. Unfortunately, the beast has an advantage over Vincent that requires Cat's help, in addition to the help of someone else who opens up old wounds from Vincent's past.
Cat gets a blast from the past as she attends her high school reunion, where she uncovers more of her past than she ever anticipated. Meanwhile, Vincent meets up with one of his old military buddies who is hiding a very dangerous secret.
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.
After Vincent's life is endangered, Cat decides they should spend Thanksgiving with her father in order to get information on Vincent's missions. However, when Gabe and Tori join the festivities, true feelings are revealed and secrets are outed. Meanwhile, J.T. and Tess get a surprise while they celebrate Thanksgiving together.
Vincent and Cat find themselves at odds on how to deal with Agent Reynolds, which forces Vincent to wonder if he is more beast than man. Cat makes a drastic move that will forever change her relationship with Vincent.