Catherine has a feisty personality. Even though she can often time be endearing towards her co-workers, she does have limits. She is known for slapping people at the drop of a dime, whether they deserve it or not. However, under her sometimes gruff exterior is a gentle understanding of the madness that can happen around the station. Catherine has also been known to be a skilled con woman and has said that she used to work her uncle's Three Card Monty hustle during the summers in her youth.Despite having all of her co-workers call her Catherine, Jimmy is the only one who regularly calls her Cathy, a respect only he seems to have earned. When Jimmy originally created his "wife candidate list", she was originally on it, though after seeing the contempt she held for the idea, he crossed her name off. One of the biggest flaws in her personality is that she can sometimes be impetuous, particularly when she is about to slap someone. When Mr. James comes over to her to see if she can find out if Ruth's breasts are real, Catherine thinks Jimmy is asking her personally, to which she responds with a swift slap.
Catherine Moves OnEditAfter portraying the character for four years and seeing her presence on the show dwindle, Alexander wanted to leave NewsRadio to more dramatic roles. Her character was celebrated as well as finally given a plot to herself in, Catherine Moves On, which was in season four, episode seven, Catherine Moves On. The plot is that Catherine has announced she is leaving WNYX, but no one actually knows/remembers why. Each character gives their own interpretation of events to the owner of the station, Jimmy James, played by Stephen Root, that would have led to Catherine wanting to quit. Most of them believe it was something that they did to set her off and make her want to leave. In the end, it is revealed that she got a job offer to be the London Correspondent for a satellite news service and that she starts the next day. The episode is a hysterical comedy and is really a great tribute to the character as well as the actress. The opening credits are even special to show all the times Catherine slapped her male co-stars and her interactions with her female co-stars. While this episode is somewhat sad, it is hard not to laugh at some of the outlandish things that the WNYX staff come up with for why she decided to leave. While Dave thinks it's because Bill eats to loud, Bill thinks it's because she was in love with him and Lisa believes it is because it to be that the demanding job of news director proved to be too much for her. There hugs all around and it is Catherine (as well as the audience) who get the last laugh on the WNYX staff. Using the romantic feelings that Joe, played by Joe Rogan, and Bill had for her, she gets them both to come to her apartment, under the guise that she wants to have sex with them. As the comedy of errors ensues, Catherine calls her apartment and says on the voicemail, “Hi Joe, Hi, Bill. If both of you can hear me right now, I am one happy woman. Goodbye!” At the end of the episode, a title card is shown saying, "Good Luck, Khandi, from all of us at NewsRadio."
Alexander's name was seen in the special opening credits for the episode, The Secret of Managment, despite this being after she had departed from the series.Khandi Alexander would return to the series for the special season 5 episode “Bill Moves On”, which addresses the death of Bill McNeal, and the real life death of Phil Hartman. Catherine reads a letter written by Bill prior to his death about how she was one of his greatest loves and that he regrets thier not being able to remain lovers. She is cut off by the rest of the cast before getting into any of the more explicit details that Bill wrote in the letter.