Grimm was last seen in Perris, California on March 31, 1986. Her mother stated that Grimm departed from her residence to purchase a pack of cigarettes and never returned.

Grimm phoned her mother periodically during the following 18 months. She claimed that she was in Wichita, Kansas and was doing well. Grimm refused to divulge her address and her mother said that her daughter sounded afraid during the conversations. Grimm called her mother for the final time during October 1987 from an unknown location. She has never been heard from again. Grimm may have resided in Wichita with Robert Masters, who was employed as a truck driver at the time. California and Texas authorities are handling Grimm's investigation. Foul play is suspected in her case.

There are discrepanies regarding the actual date of Grimm's departure from California. Some agencies list April 1986 or April 5, 1985 as the date of her disappearance. In addition, some organizations may state that Grimm's husband was the last person to see her in California. Her case remains unsolved.