Katy Mahoney is the main character and protagonist of the crime drama TV series "Lady Blue," which aired from 1985 to 1986. She is a tough, streetwise cop who is determined to bring justice to the criminals of her city, which is set in Chicago.

Katy is portrayed as a strong and independent woman who has a no-nonsense attitude towards her work as a police officer. She is often shown going up against organized crime syndicates and other dangerous criminals in order to bring them to justice. Despite facing numerous obstacles and setbacks, she is always determined to see justice served, no matter what the cost.

Katy's tough exterior belies a vulnerable side, as she is shown struggling with personal demons throughout the series. Her past is slowly revealed throughout the show, including a traumatic event in her childhood that has haunted her throughout her life.

Overall, Katy Mahoney is a complex and dynamic character who is not afraid to stand up for what she believes in. Her strong portrayal of a female police officer was groundbreaking at the time and paved the way for more female characters to be represented in law enforcement roles on television.