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On September 19, broadcast insiders revealed all four members of Melody Day will be appearing on the show. The group debuted in 2014 with their single 'Melody Parting', but they've yet to really receive the spotlight. Member Yeoeun is also known for her win on MBC's 'Mask King'.

Former Girl's Day member Jisun's appearance on 'The Unit' has been confirmed. She debuted in 2010 as a member of Girl's Day, but withdrew in September of 2011. She then joined New.FO in 2011 under the stage name JN, but she's now looking to start fresh on 'The Unit'. 

Oukid members Yooha and 1Bell are also reported to be joining the lineup of the show.

'The Unit' is set to premiere on KBS on October 28 KST. Stay tuned for updates.