KO One is a 2005 Taiwanese drama starring Jiro Wang, Calvin Chen, Aaron Yan and Danson Tang. It was produced by Comic International Productions and was first broadcast in Taiwan on cable TV Gala Television Variety Show/CH 28 on 26 November 2005 to 27 May 2006.
Before this drama was aired there was not much interests in it, due to the storyline and unfamiliar cast. Despite the new encounters, the ratings of KO One exceeded expectations. Although the ratings were not high, it brought fame to three of the four leads, who are part of the then newly formed Taiwanese boy band called Fahrenheit. This drama also brought fame to the Taiwanese artist, Tank who wrote and sang the opening and ending theme songs. The KO One original soundtrack was the best selling soundtrack of 2006, selling more than 60,000 copies in Taiwan within the first month of release.
The sequel The X-Family was broadcast from 8 August 2007 to 23 October 2007 and threequel, K.O.3an Guo was broadcast from 28 February 2009 to 27 February 2010, on cable TV Gala Television Variety Show/CH 28..