Park Kang-moo is a sincere and kind house-husband to Kang Mi-seon who is a top detective in violent crimes division. What she doesn't know is that Kang-moo is an ex-spy and was forced to leave his past life after a failed mission. As he leads a boring yet satisfying life of an house-husband, a chance encounter with Jang Hee-joo, his junior will make him to go back to his life as a spy in order to help Hee-joo save her kidnapped husband. This case gets entangled with the one Mi-seon is investigating on and she soon suspects Kang-moo of having an affair with Hee-joo. As they both get into the game without knowing the players, the danger that follows will bring them closer. How do they get out of the mess and save their marriage, forms rest of the story.
The writing is basic at it's best and after the only big reveal about the mysterious villain, half way into the film, Mission: Cross literally is devoid of any intriguing moments and the action too is quite generic to stand out. All it leaves is the two main leads to kick up the spark and the comic timing to salvage what's left but that just proves to be not enough. Even with the runtime of barely 100mins, the film gets boring and the half baked screenplay doesn't really offer anything to remember. Spoiler, the film does end on a note opening up for a sequel but there is hardly any interest left to care for it.
