A Gentleman’s Dignity is about the careers and love lives of urban professionals. It tells the story of four men in their forties who have been friends since they were eighteen, as they go through love, breakup, success and failure.
Kim Do-jin is a confident playboy who meets Seo Yi-soo and falls for her. To his surprise, she doesn’t give him the time of day and he discovers that she has a crush on his best friend Im Tae-san. He begins a one-sided love for the first time in his life and tries to win her heart.
Im Tae-san starts dating Yi-soo’s roommate, Hong Se-ra, but troubles arise when Yi-soo’s crush is revealed and when Se-ra tells him she doesn’t want to get married.
Choi Yoon is a lawyer who is still recovering from his wife’s death four years ago but begins to have feelings for Tae-san’s much younger sister, Im Meari. Meari has always had a crush on Yoon. However, Yoon refuses to give into his feelings and jeopardize his friendship with Tae-san.
Lee Jung-rok is married to a rich woman, Park Min-sook, but constantly flirts with other women which causes problems and trust issues in their marriage.
Meanwhile, a teenager named Colin comes to Korea looking for the four men and claims one of them is his biological father.