Vail was reported missing by her mother Oct. 22, 1984, after she had not talked to her daughter for several weeks. Her husband at the time said she left the country, but that has never been confirmed.
Vail received a large sum of money and some property shortly before her disappearance.
Police classify this core group of cold-case missing persons as endangered.
While hundreds of people are reported missing in Tulsa yearly, most cases are closed when the victims are found alive. Detectives are also pursuing leads in several active missing-persons investigations.
If anyone has information that could help police close these cold cases, please call Crime Stoppers at 596-COPS.