Celli was last seen leaving her parents' Grandview Heights, Ohio home on February 23, 1946. She was going to take a bus to downtown Columbus, Ohio to buy nylon stockings. Celli apparently never made it to the bus stop down the street from her home. She never been heard from again.

Celli is a graduate of Ohio State University, where she was an honors student and a member of the Spanish Club, the French Club and the Educaton Council. She can speak five languages. She was taught home economics at West Mansfield High School. At the time she vanished, she was visiting her parents' home for the President's Day holiday weekend. Her loved ones stated she was in good physical and mental health at the time she vanished and they did not believe she had left of her own accord. Celli's parents described her as a non-smoker and non-drinker and also stated she was not dating anyone when she disappeared. Authorities initially believed Celli suffered an amnesiac episode which caused her disappearance, but no evidence has been located to support this. Her family always maintained she was abducted.

A witness reported seeing a woman resembling Celli arguing with a man in a car along Olentangy River Road on the day of her disappearance. During the argument, a red shoe was thrown or fell from the vehicle, described as a red Dodge coupe with a broken window. The witness attempted to find the shoe, but couldn't. That same day, a man driving a red coupe with a broken window stopped for gas at a station on north High Street, about a mile rom the Olentangy River Road. The man had a woman in the car with him and the station attendant heard him tell her to "be quiet." He bought $2 worth of gas, paid with a $5 bill and drove away without waiting for his change.

In 1956, the Grandview Heights chief of police claimed the Celli case was "closed" because the marshal of Marble Cliff, Ohio had told him her whereabouts. The police chief said Celli was alive and her disappearance was not a criminal matter. Celli's family stated they didn't believe this information and added that the police chief had not been in touch with them since August 1946, six months after her disappearance.

Celli's case has puzzled the Grandview Heights police department for years. It is still an open investigation.