Season 1 of the show aired on tvN starting from June 16, 2019 to August 4, 2019 on Sundays at 22:40 (KST).

The Hearers' job is to listen to the different singing voices and find the correct contestant(s) that fits the theme.

On the other hand, the Villains' job is to interfere the Hearers by making them confused which in turn preventing them from getting the right answers.

Round 2 is to listen to each of the remaining 4 contestants sing a part of a song or a small medley, and their real identities are shown to only the Villains and the audience.

The Hearers will have to eventually decide on the contestant(s) out of the remaining 4 who they believe to fit the theme.