Allan was last seen leaving his place of employment, Plaza Dodge, in Brooksville, Florida on October 31, 1997. He was planning to pick up his son at his ex-wife's residence in Tampa, Florida and take the child trick-or-treating later that Halloween evening. Authorities believe that Allan arrived at his residence in the 4200 block of Canterbury Drive in Holiday, Florida at approximately 6:00 p.m. that evening. He apparently phoned his girlfriend to discuss the evening's plans, then departed from his home. There were intense thunderstorms in the area at the time he began driving to Tampa. Allan never arrived to retrieve his son and has never been seen again. He was reported as a missing person on November 2, 1997, two days after he disappeared.

Allan's red 1989 Dodge Daytona was discovered abandoned on November 25, 1997, nearly one month after his disappearance. The vehicle was located in a shopping center parking lot in Tarpon Springs, Florida. There was no trace of Allan at the scene, but bloodstains were found inside the vehicle.

At the time of his disappearance, Allan was involved in an ongoing dispute with his ex-wife over child support. He had had custody of their son since February 1996. He disappeared two weeks before he and his ex-wife were due to appear in court to settle the child support issue. Allan's mother believes the child support issue is connected to his disappearance, but this theory has not been verified.

Allan was employed as a service manager in 1997. He enjoys camping and fishing. His loved ones stated it is uncharacteristic of him to leave without warning, and foul play is suspected in his case.