Mace is a tough girl limo cab driver who goes around saving Lenny's ass pretty much throughout the movie, from driving him around in her limo when his car gets repossessed (Those damn bank errors) to beating up Gant's thugs every time he sends them to kick the shit out of Lenny. She didn't start out that way. In one of the flashbacks from the movie (when Lenny was still a cop), we see her coming home from work dressed as a waitress as her husband is being arrested, and Lenny is playing with her son. Of course, Lenny is too blind until the end to realize that she does all this for him because she loves him.
