Wise-cracking Sherry Conley (Ginger Rogers) is moved by U.S. Attorney Hallet (Edward G. Robinson) and Detective Lieutenant Striker (Brian Keith) from prison to a swanky hotel suite. They try to persuade her to "sing" against gang leader Benny Costain (Lorne Greene). Sherry first refuses to testify but changes her mind when a bullet intended for her kills a prison matron. Striker is shot when the mobster makes his last desperate effort to silence the girl.