Block B's Zico was surprised and shocked by the revelation of his ex-girlfriend on Block B's new reality TV show, "Block B's 5 Minutes Before Chaos".

The Mnet show has Block B members break idol taboos, including the 'no-dating rule'. This week's episode was about revealing secrets, and one of the Block B members revealed who Zico's ex-girlfriend is on the show.

Zico looked visibly shaken when one of the members held up a picture, saying, "Zico's ex-girlfriend is one of the people on this picture". Zico tried his best to keep the picture from showing, but it was shown without a hitch. Other Block B members who had no idea about Zico's past expressed surprise.

Block B also reveals their rooms, including their sleeping quarters and their recording studio. They also show their face without the makeup.

The format of the show is that Block B, while they do record the video clips necessary for the show, has no idea how their clips would be edited. They watch the show with the viewers and the audience and comment on the show via social networks such as Facebook and Twitter. These features make "Block B's Five Minutes Before Chaos" a revolutionary show.