Handsome Boys of the 20th Century

The show features five members from four disbanded or inactive "first-generation" K-pop idol groups, which debuted during the 1990s: H.O.T. (1996–2001; 2018–Present), Sechs Kies (1997–2000; 2016–Present), NRG (1997–2006; 2017–Present) and g.o.d (1999–Present).