To get a realistic portrayal of North Korea, the writer, Park Ji Eun, carried out interviews with North Korean defectors.
Hyun Bin has been in a relationship with actress Son Ye-jin after "Crash Landing on You" concluded. They married 2022 March 31. On June 27, Son announced that she is pregnant with the couples first child.
In one scene a soldier is seen playing a computer game and royally beating an unseen competitor. When the scene switches viewers find his competitor is male-lead Hyun Bin. As he is getting pwned, they play the theme song from the series MEMORIES OF THE ALHAMBRA, in which he played the lead role as a gamer in virtual-reality-gone-mad. That song was played throughout the series any time the game was about to get dangerous... and was a "tip of the hat" reference to his lead in that series.