Mad Dog is a South Korean television series starring Yoo Ji-tae, Woo Do-hwan, and Ryu Hwa-young. It aired on KBS2, from October 11, 2017 to November 30, 2017 on Wednesdays and Thursdays at 22:00 (KST) for 16 episodes.

Yoo Ji-tae is a South Korean actor, film director and screenwriter. After a stint as a fashion model, Yoo launched his acting career in 1998 then rose to fame through the films Attack the Gas Station (1999) and Ditto (2000). In the succeeding years, he gained acting recognition by working with acclaimed directors such as Hur Jin-ho in One Fine Spring Day (2001), Park Chan-wook in Oldboy (2003), and Hong Sang-soo in Woman is the Future of Man (2004). Yoo began directing short films in 2003, which were well received in the film festival circuit. His feature directorial debut Mai Ratima was released in 2012.