"Seed of Chucky" is a sequel to "Bride of Chucky." It follows the story of Glen, a ventriloquist dummy looking for his parents. When he discovers that he is a child of the murderous dolls, Chucky and Tiffany, he wakes them with an amulet. Horrified at the fact that Glen has no taste for killing, Chucky and Tiffany decide to show him how great it can be.
At the beginning of the movie, Glen has dreams of killing. Determined to find out why, he goes in search of his parents. He discovers a movie is being made about them, and he finds them on set at a Hollywood studio. After waking them, his mother, Tiffany, is excited to hear that Jennifer Tilly is playing her in the movie. She wants a human body and attempts to transfer her soul into Jennifer's body. Throughout the movie, Tiffany refers to Glen as "Glenda" and Chucky calls him "Glen" because they are not sure whether he is a boy or a girl.
Toward the end of the movie, Jennifer has been impregnated by Chucky and is going to have twins. Chucky wants Jennifer, Tiffany and Glen dead; however, before he can accomplish this, Glen uses an ax to hack him to pieces. Tiffany manages to transfer her soul into Jennifer's body, while Glen transfers his soul into the twins, with his gentle side going into the boy and his killer side into the girl. At the end of the movie, he is glad to finally be a normal child with a parent.