It was aired on the Mnet channel, IQIYI, AbemaTV, tvN Asia, or YouTube depending on the viewer's region.

A production by Mnet's parent company CJ E&M and its subsidiary Studio Take One, as well as in collaboration with game developer and publisher NCSoft, the aim of the competition was to debut a new 9-member K-pop girl group consisting of trainees and idols from China,[b] Japan, and South Korea.

[4] The "planet" theme of the show was derived from a new collaboration between Mnet and NCSoft's new platform called Universe which is centered around K-pop.

Contestants who are selected or voted to be the Planet Top 9 (designated P1 to P9) can reorganize cells to try and lower the chances of elimination.

The theme song, "O.O.O (Over&Over&Over)," was released on July 12, 2021, accompanied by a performance by the Korean group with Kim Dayeon as Center.

Another version of the performance featuring the Chinese group was released on July 14 with Shen Xiaoting as Center.

[citation needed] The series was presented by Yeo Jin-goo,[6] dubbed as the "Planet Master."

Color key: Planet Pass was a vote by the mentors, in which eliminated contestants could be brought back to the show.

Yeo Jin-goo announced the newly formed girl group name to be Kep1er (케플러).

[16] The group's debut performance at the 2021 Mnet Asian Music Awards on December 11 was also cancelled as a result, as well as some members testing positive for COVID-19.

In May 2024, it was revealed that all members, except for Sakamoto Mashiro and Kang Ye-seo, renewed their contracts with WakeOne.