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You gentlemen aren’t really trying to kill my son, are you?
— Clara Thornhill ‧ North by Northwest
Behind the line May contain spoilers.
Our reading
An editorial interpretation.
Addressing the men politely as gentlemen, the speaker asks in disbelief whether they truly intend to kill the speaker's own son. The courteous phrasing sits oddly against the grim subject, and the "really" and closing tag question suggest a parent trying to make sense of the danger.
Context reviewed