In Japan there is a music producer named Johnny Kitagawa who has been churning out artificially manufactured boy bands since the early 1960s. Many of his boy bands have become hugely famous and popular, but the most successful of them all is SMAP, the group that launched the career of Japanese all-media superstar Kimura Takuya.
Apparently the name "SMAP" (pronounced "sumappu" in Japanese, was originally supposed to be an acronym for "Sports Music Assemble People" (sic), but this has long since been forgotten by everyone involved. Originally the group had 6 members, but one of them got lost pretty early on, and today the group consists of Kimura, Masahiro Nakai, Tsuyoshi Kusanagi, Goro Inagaki, and Shingo Katori.
The members of SMAP are ubiquitous in Japan, as you pretty much cannot cross the street without seeing them in some sort of advertisement or else singing and dancing on some sort of screen. And it's been like this for twenty years now, ever since their founding in 1991.
Believe it or not, SMAP was actually not successful at first, because ironically, music is probably their weakest point, but staring roles on a series of television variety programs in the 1990s, along with the general likability of the members and the handsomeness of Kimura (known as "Kimutaku" to his fans), saw them soar in popularity until they were the most famous group in Japan.
Although the members have done individual side projects (Kimura in particular wound up with a significant acting career), the group never broke up, and even though their TV shows were always more popular than their music, they never gave up on music and eventually got halfway decent at it. To date they have released more than 20 albums and countless singles. Their most famous song is 2003's Sekai ni Hitotsu Dake no Hana ("A Flower Unlike Any Other in the World"), an insanely catchy ditty that is the ninth best selling single in Japanese music history.
Through it all, the key to SMAP's success was that they reached beyond the traditional boy band demographic of young women and teenage girls to genuinely appeal to all sectors of Japanese society. Of course they had the minimum of singing and dancing chops necessary to be selected to a hand-selected boy band, but it was really their self-deprecating sense of humor, exemplified by their willingness to go on TV and do all manner of silly things, that so endeared them to the masses.