This is not a mystery, but a very good thriller! Then why there's Mystery tag?<br /><br />Well apart from that, It's really a very good movie. A chilling thriller. I didn't feel this was a total film-noir.<br /><br />Sinatra plays a very good role as Baron the assassin. The movie portrays Baron's psychological struggle with his captives, and presents an interesting portrait of what nowadays is a controversial matter, the function of firearms in the home.<br /><br />Ironically, Sinatra's character presents himself as a "war hero," while Sinatra was 4-F during World War II and Sterling Hayden served with the United States Marine Corps and received the Silver Star for his gallantry in the European theatre.