Mirror is a Hong Kong Cantopop boy group formed through ViuTV's reality talent show Good Night Show - King Maker in 2018. The group consists of twelve members: Frankie Chan, Alton Wong, Lokman Yeung, Stanley Yau, Anson Kong, Jer Lau, Ian Chan, Anson Lo, Jeremy Lee, Edan Lui, Keung To, and Tiger Yau. They debuted on 3 November 2018 with the single "In a Second" (一秒間).

Cantopop is a genre of pop music sung in Cantonese. Cantopop is also used to refer to the cultural context of its production and consumption. The genre began in the 1970s and became associated with Hong Kong popular music from the middle of the decade. Cantopop then reached its height of popularity in the 1980s and 1990s before slowly declining in the 2000s and shrinking in the 2010s. The term "Cantopop" itself was coined in 1978 after "Cantorock", a term first used in 1974. In the 1980s, Cantopop reached its highest glory with fanbase and concerts all over the world, especially in Macau, Mainland China, Taiwan, Singapore, Malaysia, South Korea, and Japan. This was even more obvious with the influx of songs from Hong Kong movies during the time.