What do Gong Yoo, T.O.P. and Kim Soo Hyun have in common? They all played North Korean spies and defectors this year. Recent news reports have noted a rise in the number of real North Korean defectors. And one place more North Korean expatriates are turning up is as fictional characters in South Korean films.

Tensions between North and South Korea escalated after Kim Jong Un was declared North Korea's supreme leader in 2011. The new leader issued threats that South Koreans did their best to ignore. But it's hard to completely ignore the idea that an attack could be a reality. And it's also hard to ignore the growing number of defectors. According to England's Financial Times more than 25,000 North Korean defectors have so far risked their lives to head south.

The ever-present threat of a strike and the number of defectors may not be preferred topics of conversation in Seoul but the two subjects have found their way into the plots of a few recent South Korean films.

In Gong Yoo's grim and gritty action film "The Suspect," he's an abandoned North Korean spy who makes a new life for himself in South Korea. But he can't live quietly after he becomes a suspect in a CEO's murder. The film was released last week and has earned positive reviews.

Another 2013 spy thriller is "The Berlin File," starring Ha Jung Woo as a North Korean spy in Berlin. When Ha Jung Woo's character, along with his wife played by Jun Ji Hyun, discover they are about to be purged, they try to escape with both North and South Korean agents on their trail. The film had a strong opening with 2.8 million tickets sold in just over a week.

The film "Commitment," starring BigBang's T.O.P. a.k.a. Choi Seung Hyun, details the horrors of suddenly being on the wrong side in North Korea. In the film, he plays a 19-year-old student who is forced to become a killer after his father is falsely accused. He must become a spy and an assassin in South Korea. The film reached first place in the box office.

Younger audiences enjoyed the box office hit "Secretly, Greatly," which starred Kim Soo Hyun, Park Ki Woong and Lee Hyun Woo. The three actors played North Korean spies sent down south to carry out a mission. They like it in the South and settle in nicely. When it is decided that the mission should be abandoned and they should be eliminated, the three must do what it takes to save their own lives. The film recorded the highest single day opening of all time in the Korean box office. Many of those younger viewers are a few generations removed from the conflict that split the peninsula.