In 1960 he left reporting and moved to New York for the advertising industry, becoming copywriter and creative executive for a series of agencies such as J. Walter Thompson, Young & Rubicam and BBDO.

Not surprisingly, he specialized in advertising copy for the motor trade, an area of booming competition in the car-obsessed economy of 1960s America.

[3] When interviewed about what impact the foreign policy issues raised by Missing had on audiences, Stewart commented: "Movies have a tendency to really heat up the emotions.

[2] He wrote or co-wrote the screenplays for the Tom Clancy trilogy of Jack Ryan films: The Hunt for Red October, Patriot Games, and Clear and Present Danger.

Hostiles, released in December 2017, was based on a manuscript written by Stewart in the 1980s and brought to life by director and co-writer Scott Cooper.