Sparks: The Price of Passion(1990)

A female mayor of Albuquerque gets embroiled in a fight over the development of a new economic center. In the midst of this, she receives blackmail photos of an overnight fling she had with a stranger and threats of blackmail. On top of all this, the city is under siege by a serial killer who hunts powerful women. When the FBI moves in for the investigation, the chief officer turns out to be the stranger.