Part 1 focused on the boot camp in 2019 with 26 contestants and was broadcast exclusively on Hulu Japan from January 31, 2020 to March 27, 2020.

In February 2019, JYP Entertainment and Sony Music Entertainment Japan announced that they were creating an audition program titled Nizi Project to create a Japanese girl group aimed at a global audience, with plans for the group to debut in November 2020.

[2][3] The second round of auditions took place from July to August 2019 in eight locations in Japan as well as Hawaii and Los Angeles, with 26 contestants selected by JYP Entertainment founder Park Jin-young.

[8] A version of the show, presented in the "perspective of the [host] and [Park] as the producers", was broadcast as a series of documentaries under the title Nizi no Kake Hashi (虹のかけ橋); the show was hosted by Daimaou Kosaka, with interviews from Park and the Nizi Project contestants, and was broadcast from April 17, 2020 to June 26, 2020.

[3] A special feature of Nizi no Kake Hashi was broadcast on June 26, 2020, with announcer Keisuke Mori co-hosting the segment with Kosaka.

[2] Nizi Project Part 1 focused on the auditions in July and August 2019 and the Tokyo boot camp in September 2019.

[2][3] The second round of auditions took place from July to August 2019 in Sapporo, Sendai, Tokyo, Nagoya, Osaka, Hiroshima, Fukuoka, and Okinawa, as well as Hawaii and Los Angeles in the United States.

[1] During the second auditions, Park and a panel of judges selected 26 contestants, which they awarded with Nizi pendants, and they would attend a boot camp in Tokyo that lasted four nights and five days.

[4] If Park felt a contestant satisfied one of the categories, he would award her a triangular cube to fill her Nizi pendant.

[24] The top 14 contestants qualified to attend a boot camp in South Korea for six months, beginning in December 2019.

[25] In episodes 15 and 16, the contestants are invited on a day out under the pretense of having a picnic, only for it to be a sports festival aimed to foster their physical endurance and artistic expressions.

[26] Additional cubes were awarded to Mako Yamaguchi (1st), Rio Hanabashi (2nd), Mayuka Ogou (3rd), Rima Yokoi (6th), Nina Hillman (8th), and Riria Ikematsu (9th) as runner-ups.

[33] On July 12, 2021, Park held a press conference announcing that Nizi Project will have a second season to create a Japanese boy band set for debut in March 2023.

[36] Auditions will take place from November to December 2021 in eight cities in Japan, as well as New York and Los Angeles in the United States, and Seoul in South Korea.