Na-Yeon is a bright woman. She supports her boyfriend Tae-Joon, who is from a poor background, and has even given up entering a university. But Tae-Joon dumps her for his success and goes with Se-Jin, who is a granddaughter of Baekdoo Company president. Do-Hee is Na-Yeon’s twin sister. She is arrogant and tough. Do-Hee works as a reporter at a weekly magazine. After Na-Yeon’s death, Do-Hee decides to take revenge. She takes on the identity of her sister Na-Yeon. Do-Hee then meets Hwi-Kyung, who is successor of Baekdoo Company.

A Thousand Days' Promise is a 2011 South Korean traditional melodrama about a woman who is losing her memory and the loving man who stands by her side. Written by famed drama writer Kim Soo-hyun, it aired on SBS from October 17 to December 20, 2011 on Mondays and Tuesdays at 21:55 for 20 episodes.

Newspaper journalist Shunsuke Akiba is transferred to the cultural desk and put in charge of shogi. He meets Nobushige Sanada, a 33-year-old aiming to be a professional shogi player by achieving the rank of 4-dan or more. Sanada is over the age limit as he could not achieve 4-dan by the age of 26, and is now trying to take an exam for admission to 3-dan. Akiba supports Sanada's attempt to become a professional shogi player and becomes interested in the game.