Ishigami comes home from work and discovers his wife dead. Just then, he receives a phone call from his wife and falls in utter confusion. Unexplainable things keep happening as Ishigami struggles to find his wife. Gradually, Ishigami realizes all his memories are gone and finds himself acting like someone else. What is his true identity?

Marriage Blue is a romantic comedy film that follows the misadventures of four engaged couples in the week leading up to their weddings. Tae-kyu is a former professional baseball player who currently coaches for a minor league team. His girlfriend Joo-young runs a successful urology clinic. They've broken up once before then gotten back together, and now they're about to get married. But a week before their wedding, Tae-kyu learns something about Joo-young that makes him feel betrayed and jealous. Growing increasingly neurotic, he becomes obsessed with finding all about her exes and dating past. Chef Won-chul and nail artist So-mi have been a couple for seven years and their wedding day is fast approaching. But feeling that something is missing in their life, So-mi suspects that Won-chul doesn't feel passionate towards her anymore and merely regards their relationship as a comfortable living arrangement. Several days before getting hitched, So-mi travels to Jeju Island for a nail art ... Written by Rainer Klein