Despite its title, "The King" is not a film about a king.

It's a film about an ambitious prosecutor who uses his colleagues and gang member friends to get ahead. The character is ambitious because he suffered through a difficult early life, but that desire to escape his childhood often overwhelms his sense of justice.

Jo In Sung plays the prosecutor and it's his first film in seven years. His last film role was in "A Frozen Flower," when his character was caught in a love triangle between a king and his queen. Since Jo's release from military duty in May 2011, he has starred in two successful dramas, "That Winter The Wind Blows" with Song Hye Kyo, and "It's Okay That's Love" with Gong Hyo Jin.

Being a highly desirable commercial model has allowed him to be very particular about the roles he takes.

On January 2 it was announced that Jung Woo Sung has been cast as a senior prosecutor in the film. That means his character will be the superior of the character played by Jo In Sung.

Jung Woo Sung's agency, Red Brick House, told the Korean media outlet XSports news that Jung Woo Sung's participation has been confirmed.

Jung Woo Sung's last k-drama was the melodrama "Padam, Padam: The Sound Of His And Her Heartbeats" with Song Ji Hyo and Kim Bum. He's made four films since then, playing a baduk player in "Divine Move," a detective in "Cold Eyes," a professor in "Scarlet Innocence," and a man who lost his memory in "Don't Forget Me." He directed a short film on his own in 2012 and along with some friends directed an omnibus of short films in 2014.

Two more major roles need to be filled in "The King." The producers must find an actress to play Jo In Sung's wife and an actor to play a gang member. The production crew hopes to wrap up the casting details in the next few weeks as the film is scheduled to start shooting at the end of January.

Han Jae Rim, known for directing "The Face Reader" and "Rules of Dating" will direct the film.