Cat Chandler is an NYPD police detective whose mother, Vanessa Chandler, worked on a secret government project that brought her into contact with a beast when her mother was murdered.

That beast, Vincent Keller, followed Cat for years until she discovered him while looking into the murder of her mother. She fell in love with the beast, and Vincent and his friend J.T. Forbes helped Cat and her partner Tess Vargas solve crimes before Vincent was kidnapped by Cat's birth father and had his memory erased.

At the beginning of Beauty and the Beast Season 2, Cat found Vincent and she and her friends have been working to help him find his memory and cure him of his beastliness, as Cat was able to do with another beast, Gabe Lowen, who is now working with them as the new police chief.

Cat learned her father, Thomas, was not her birth father but does not know Vincent is working for him. Her sister Heather took a job in Florida, leaving Cat with only her friends to rely on.

Cat has had moments of doubt about her future with Vincent, but has never stopped loving him.