While it's not Yi Sun Shin's greatest naval victory, it is nevertheless a significant event in Korean history. The sea battle is beautifully depicted, though conflating details from his other naval battles, it still gets some key facts right, and about the famous turtle ships and Korean and Japanese fighting tactics. More importantly, you get a different look than the western navies that relied on sail and wind.
The movie feels a bit rushed at the start to set the stage. When you have a movie about a naval battle, I can understand that you can't spend a lot time on the buildup of events leading up to it, but it could be confusing for non-Koreans who did not grow up learning about it in school. There are of course also lots of manufactured drama, but that's to be expected--this is not a historical documentary.
This is the prequel to "The Admiral: Roaring Currents" (2014), which depicts Yi Sun Shin's most famous victory at Myeongryang Strait some five years after the events in this film.
