On the 1st of April episode of SBS "K-pop star audition" the contestants gets the chance to each train under SM Entertainment (BoA), JYP Entertainment (Park Jin Young) and of course YG Entertainment (Yang Hyun Seok). The top 5 remaining got the rare chance to be trained under the big 3 agencies and they were in for a treat as a surprise mentor helped them out when they visited YG Entertainment.

One of YG Entertainment's hit producer Teddy made a special appearance in the episode. When the contestants arrived in the building, Yang Hyun Seok said he was going to call out a friend and it turned out to be Teddy to the contestants surprise.Teddy is known for making hits for the agency and the contestants were able to record songs with him to be their mentor. On the show Teddy worked with the contestants for over 6 hours of recording songs.

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