Every leap year for the past twenty-four years, a serial killer has been active on Australia's eastern and southern coast. Three women are strangled with a pair of stockings every four years on the exact dates, the 29th of February and the 3rd and 6th of March. Chief Superintendent Bill Clements has been on the killer's trail since the first murder when he was a young senior constable at the Southern Palms Police Station. Now, the killer has returned to the southern suburbs of Sydney. Detective Senior Sergeant Tank Dodge and his team are tasked with arresting the perpetrator, nicknamed The Stocking Strangler, before they disappear for another four years. Hindering their project is an international hitman, known worldwide by the alias, the Ghost, who is murdering people associated with a diamond mine in South Africa who are also suspects in the strangler case.

Intertwined with the murders is the reappearance of the Satanic church that Tank thought his team had disbanded the previous year. Once again, forensic pathologist Katie Phillips and computer analyst Ned Patterson assist the homicide unit as they narrow down the suspects, including twin illusionist brothers, a billionaire, a solicitor, a blind psychic and a corrections officer.