The film is a continuation of the 2001 television series, A Step into the Past, which was based on Huang Yi's novel, The Chronicles of Searching Qin.

After being wrongfully imprisoned for many years, Ken swears to travel back to the past and become the Emperor to make up the life wasted while incarcerated.

Just when Qin Shi Huang was uniting the six kingdoms, Ken makes a surprise attack on him, he has no choice but to go to his former mentor.

[4] In March 2018, it was announced that aside from Koo, Jessica Hsuan and Raymond Lam will also be reprising their roles from the series and production was to begin at the end if 2018 with budget of US$45 million.

Aside from Koo, Hsuan and Lam, series cast members Joyce Tang and Michelle Saram were also present at the event, confirming their participation in the film.