 Kang continued acting on television but his 2006 dramas "Fireworks", about two cosmetics firm employees who plot revenge against their exes (opposite Han Chae-young), and "90 Days, Time to Love", about a terminally ill married man who's in love with his cousin (opposite Kim Ha-neul), received low viewership ratings.In 2007, he and Han Ji-min starred in "Capital Scandal", a period drama adapted from Lee Sun-mi's novel set in Japanese-occupied Korea.His portrayal of a carefree playboy who transforms into an independence fighter garnered positive reviews.