Prime Suspect 4 - Scent Of Darkness [1996]
DVD movie

The Scent of Darkness: Jane Tennison sent George Marlow down for six brutal murders. Now, two more women turn up dead with the same markings, doused in the same perfume. Is this a copycat killer, or did Tennison get it wrong? The D.C.I. working under her supervision is convinced she lacks the proper objectivity and is jeopardizing the investigation. But even off the case and suspended from the force, Tennison continues her search. Abetted by Richard Haskins, Tennison races against time to find the third victim, held alive somewhere to fit a three-day pattern. How did the copycat get access to confidential information about Marlow's killings unless he was the killer all along?