'PD Notebook' unveiled the conversation that they had with PD of Idol School. 

In the MBC's 2 PM News, Cho Chul-young, PD of 'PD Notebook', appeared and talked about the controversy of Idol School's operations and the controversy over Produce manipulation. 

Lee Hae-in, a trainee who starred in the Idol School, joined the program. 

Lee Hae-in made her appearance in PD Notebook on October 15th and exposed hidden truth about Idol School. 

In the program, Lee Hae-in explained, "At first, they told me not to go to the audition venue where the 3,000 people were trying out. They told me 'You don't need to go,' so I wasn't preparing. But the day before filming, the writer in charge told me that I needed to go because I was relatively well known.

She added that if the contestants were asked where they'd auditioned, they wouldn't be able to reply because they hadn't auditioned. She said that most of the 3,000 people who auditioned had just been used for the show.

Cho Chul-young said, "I talked to the PD of Idol School and he said it is because the system divides general audition and special audition." 

"The program PD said that the audition of 3,000 people in the 'PD Notebook' was for the general audition. Separately, the special audition was also conducted."

"However, as a result of coverage, it was just one person who was selected out of these 3,000 contestants. This means the rest was selected at the special audition."