She was played by Barbara Alyn Woods.
Dyan Emery is an actress who was part of the cast of the sitcom, Buds, but she was looking to audition for a big movie role. When rumors of head writer Ricki Vardian planning to let go of one of the cast members surfaced, Dyan was hoping to be released so she could do the movie, which Dyan revealed was directed by Rob Reiner. Dyan learned in a phone conversation with her agent that a lawsuit was preventing her from her movie deal. She confronted Ricki about the lawsuit, only for Ricki to state that her husband, Leo Vardian, was behind it. In actuality, Ricki filed the suit for breach of contract, as Dyan was signed to a four year deal to remain on the show. Dyan confronted Ricki again in her office, demanding that she write her off for a few months so she could do the film, but Ricki refused. In a fit of rage, Dyan took Ricki's new laptop computer and struck Ricki's head, killing her instantly.
After the murder, Dyan regained possession of what she thought were her glasses (which Ricki told her to wear for the show). In actuality, as Jessica Fletcher revealed, Dyan had taken Ricki's prescription glasses, which looked similar to Dyan's except that Ricki's glasses had immense magnifying power. The villainess was caught by Jessica in Ricki's office, as she was attempting to get her own glasses back. Dyan originally denied the claim that she killed Ricki, only for Jessica to reveal that Dyan slipped up when she mentioned Ricki's new laptop to her on the morning after the murder. After attempting to get her glasses back, Dyan was stopped by police, and later confessed to killing Ricki, stating that she deserved what she got for ruining her career. Dyan also confessed to lying about her age, as after Jessica stated that she was 29, Dyan revealed that she tells People Magazine that, and she's really 36. She felt the role was her last chance and she killed Ricki believing that it would increase the chances of her getting the role, which she fittingly said was a part that "any actress would kill for." Dyan was later arrested (off-screen) for killing Ricki.