A group of spies, the 5446 Corps were trained by North Korean special forces since their youth, with a goal of unifying Korea. They are ambitiously dispatched to South Korea, where each disguises himself as a fool, an aspiring singer, and a high school student. Passing boring time without receiving any orders from the North, they gradually get used to life as ordinary neighbors in a small town. Due to the events of the Second Battle of Yeonpyeong, South Korea demands the names, location, and rank of 30 North Korean spies active in South Korea, promising financial aid to the North on the condition that Pyongyang turns in their spies. To prevent the elites from falling into enemy hands, the North Korean government orders dozens of active duty spies to take their own lives. Meanwhile, their North Korean army instructor Kim Tae-won crosses the border to eliminate those who refuse to comply. 你们考虑过金三胖的感受么！。【隐秘而伟大】（上）伟大的牺牲和隐秘的情谊。满满都是爱。基的伟大，死的光荣。隐秘而伟大的咸鱼。【隐秘而伟大】（下）演员魅力造就的精彩。如果可以，元柳焕宁愿东九一辈子。《隐秘而伟大》：既不隐秘也不伟大，倒是可怜（6/10)。来呀搞基呀。三两个美少年来搞基，十万个腐女都湿到。 两年前，朝鲜5446秘密特殊部队派出五星组组长元柳焕（金秀贤 饰），潜入韩国某个村庄担当间谍。元化名方东久，以傻子的身份在一位吝啬的大妈家落脚，他清楚村中每一个人的身世和动向，同时为了不露马脚不得不经常做出一些傻里傻气令人啼笑皆非的事来。随着金正日离世，祖国方面似乎发生些许变化。当年与元互为竞争对手的黑龙组组长李海浪（朴基雄 饰）以及视元为导师恩人的后辈李海真（李玹雨 饰）相继出现在村中。孤独的东久在两位同志面前会稍稍作回自我，而在和“敌国”百姓的相处中，他心中的冰冷也慢慢地发生改变。 某天，一道针对5446部队间谍的命令传来，三个年轻人的命运迎来了最严峻的关隘……
