Mac's closest friend from France, a high-ranking police inspector who recently married a San Francisco socialite, comes to town to show her off and talk business with his wealthy father-in-law. Mac can't give his buddy the royal treatment because he's just arrested a bullying lawyer for witness intimidation. The lawyer, from the inside, apparently hires a gunman to follow Mac around and fire warning shots at him. When Mac and Sally attend a fancy-dress ball, the inspector's wife (herself an old friend of Mac's) asks to talk to Mac on an outside balcony. A rifle shot ...