Millie Bingham Stafford (Lois Chiles) is the main villainess from "The Return of Preston Giles," episode 7.07 of Murder, She Wrote (airdate November 18, 1990). She is the wife of Kendall Stafford, who (along with Ross McKay) runs the Coventry House Publishing Company, and she is an investor in the company, using her family's money to do so.
When she found out that comptroller Martin Bergman had been blackmailing Kendall regarding his embezzlements, Millie--upset that her money was used to pay off Bergman--silenced him for good by killing him; stabbing him to death after a confrontation. Preston Giles, the killer from the pilot episode who McKay had released on parole, was under a cloud of suspicion regarding the murder, but at episode's end, he orchestrated a trap that led to Millie being revealed as Bergman's killer.
The villainess intercepted Preston's call to Kendall, and later pointed a gun at Preston, demanding the evidence of Kendall's misdeeds. After being informed that Preston had the files locked away and only he could get to them, Millie fired two shots at Preston, killing him. Millie was quickly apprehended after her latest murder and arrested.