The Red-Light Sting (1984)

Government agent Frank Powell (Beau Bridges) is determined to bring down racketeering crime lord Oliver Sully (Harold Gould) but cannot find any evidence. Powell concocts a plan to have the Justice Department buy a brothel, set up a professional call girl named Kathy Dunn (Farrah Fawcett) as a hostess, and get the crime boss on extortion.