是一部悬疑剧，讲述了在与外部隔绝的私立高中，7名学生收到“匿名书信”后八天时间里发生的神秘杀人事件。
在第二季中，故事继续双线并进。在1945年的大阪，善慈被迫在二战期间为家人的生存做出危险的决定。而在1989年的东京，白所罗门从头探索全新的开始。
讲述了18岁的少年泰柱和国义的兄弟罗曼史。在剧中，韩基燦将饰演财阀家族的独一无二的继承人，公认的皇室家庭拥有魔性魅力的泰柱一角。张义秀则将饰演拥有健壮体格，无论何时都守护在泰柱身边的朋友兼贴身保镖的囯义一角。
最高学历只有高中鉴定考试，外语能力全无、特长全无、技能全无的张克莱（任时完 饰），孤独的人生里除了围棋一无所长。少年时因为家庭变故，报考韩国棋院研究生落选后，一直自暴自弃、碌碌无为。在26岁还在打零工的他，凭借关系空降进入综合贸易公司变成营业3组的一名实习生。入职第一天的张克莱连复印机都不会使用，接电话这种小事也要求助同是实习生的安英依（姜素拉 饰）。初入职场的他面对周围外语水平一流、工作能力卓越的同事们，马上被巨大挫折感包围，觉得自己格格不入、无地自容。同时，张克莱空降兵的特殊身份曝光后，马上受到了同期实习生们的质疑和排挤。顶头上司营业3组的吴科长（李圣旻 饰）也对张克莱的身份耿耿于怀。这让张克莱认识到一无所有的自己，唯有比所有人都要努力才能在这里生存下去…… 本片根据尹泰浩作家的同名网络漫画改编，该漫画被称为“工薪阶层教科书”。
When high school teacher Na Aejoon shows up for work on an ordinary day, he never expects to bump into his favorite celebrity in the hallway. But when his school becomes a filming location for a show starring Choi Siyeol, his bias from the idol group A-One, that's exactly what happens! If that's not enough to give a fanboy a heart attack, Siyeol takes an interest in Aejoon and asks him to join the show as his "co-teacher." Desperate to keep his fan life a secret, Aejoon is forced to put his acting skills to the test, and not just on camera. But as he spends more and more time with Siyeol, the deception becomes harder to keep up. Not to mention, he might not be the only one keeping secrets…
