Gang said that he decided to play the mischievous titular character in the action fantasy Jeon Woo-chi: The Taoist Wizard because "he wanted to work on a fun movie, as he was emotionally drained while formerly having worked on several serious films. The Choi Dong-hoon film turned into a holiday blockbuster, selling over 6 million tickets over the winter season despite opening in theaters only a week after the release of Avatar in Korea. In 2010, he was cast opposite veteran actor Song Kang-ho in Jang Hoon's spy film Secret Reunion. It became one of the biggest Korean box office hits of 2010, with over 5 million tickets sold. He then joined the Busan-centered omnibus Camellia, starring in Jang Joon-hwan's short film Love For Sale.