Somin and BM are in a big relationship for about 4-5 years. Time passes happily when BM is suddenly proposed for a huge job position in America that made him leave without Somin and their best friends knowing when he will return. As the time goes by, his return will be hidden from Somin, and Jiwoo and her boyfriend ,J.seph ,will help him prepare the surprise he made for Somin. What kind of surprise is BM hidding? Will Somin forgive BM for being absent for so long?