Veronica Mars is the fictional protagonist, occasional narrator (through voice-overs), and antiheroine of the American television series Veronica Mars, which aired on UPN from 2004 to 2006 and on The CW from 2006 to 2007. The character was portrayed by Kristen Bell through the duration of the series. Following the show's cancellation, Bell reprised the role in the 2014 film continuation. The character, created by Rob Thomas, was originally male and the protagonist of his unproduced novel Untitled Rob Thomas Teen Detective Novel, which eventually became the basis of the series. After the work's transition from novel to television series, Thomas changed the character's gender from male to female because he believed that a noir piece told from a female point of view would be more interesting.

Before the show starts, Veronica's best friend, Lilly Kane, has been murdered, and her father, Keith Mars, has lost not only his position of sheriff in the fictional town of Neptune, California, but also his reputation, status, and wife. The series begins with Veronica at the bottom of her posh high school's pecking order, having lost her popular status and popular friends because her father accused her boyfriend's father of involvement in the murder.