Elizabeth Montgomery and Lizzie Borden were sixth cousins once removed, both descending from 17th-century Massachusetts resident John Luther. Rhonda McClure, the genealogist who documented the Montgomery-Borden connection, said, "I wonder how Elizabeth would have felt if she knew she was playing her own cousin."
Elizabeth Montgomery used prescribed eye drops to make her pupils look smaller, so they would look like Lizzie Borden's eyes after her morphine injections.
In 1976, Elizabeth Montgomery told reporter Joan E. Vadeboncoeur about a letter she received after the film aired which left her perplexed. "One guy wrote a critique that went on for three pages. It was very articulate. I put it down and looked at the envelope and it was from a state institution. I'm wondering what he was in for. He didn't tell me."
The movie originally aired on ABC as a Monday Night Movie of the Week.
The European theatrical version of the movie shows Elizabeth Montgomery's nudity during the scene when she kills her parents. In that version she is shown standing naked, covered in blood, holding an ax. In the ABC version, careful editing implies her nudity while never actually showing her naked.