New York City, 1950. Viviana Valentine is Girl Friday to the city's top private investigator, Tommy Fortuna. The clients can be frustrating, and none more maddening than fabulously wealthy Tallmadge Blackstone, who demands Tommy tail his daughter, Tallulah, and find out why she won't marry his business partner, a man forty years her senior. Sounds like an open-and-shut case for a P.I. known for busting up organised crime - but the next day, Viviana opens the office to find Tommy missing and a lifeless body on the floor. The cops swoop in and Detective Jake Lawson issues a warrant for Tommy's arrest. Desperate to clear Tommy's name, Viviana takes on the Blackstone case herself.