What film directed by Don Mancini has the main character of a murderous doll and is the fourth installment in its francise?  
Tiffany (Child's Play): Tiffany Valentine-Ray (also known as "The Bride of Chucky") is a murderous doll and an antagonist featured in the fourth, fifth, and sixth installments of the "Child's Play" franchise of horror films. Tiffany (Child's Play):  She is portrayed by Jennifer Tilly in both live-action and voiceover in "Bride of Chucky", "Seed of Chucky" and "Curse of Chucky". Bride of Chucky:  The film is written by Don Mancini and directed by Ronny Yu, and stars Jennifer Tilly (who plays and voices the title character Tiffany) and Brad Dourif (who voices Chucky), as well as John Ritter, Katherine Heigl and Nick Stabile.
Bride of Chucky