Who won on the May 20 installment of MBC's 'Duet Song Festival'?  Today's episode featured the return of a previous winner, B1A4's Sandeul, who had been unable to make last week's recording because of his schedule - but he's back now!

Last week's duo that was voted as the pair audience most wanted to see again was Changmin and Jun Gun Ho who performed Lee Sun Hee's "Meet Him Among Them" for 404 points.  After that was Son Seung Yeon and Jo Ye In's performance of 2NE1's "Ugly" which earned them the first spot with 411 points!  

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The current first place pair then chose Lee Suk Hoon and Lee So Ri to go next.  The two did a beautiful and powerful rendition of Jang Hye Jin's "To Me," earning them the first spot with 427 points!  Lee So Ri was touched to tears.

Then were VIXX's Ken and Choi Sang Yeop, the duo that won last week while reigning duo was absent due to Sandeul's schedule.  The two performed Kim Gun Mo's "Seoul's Moon," but were unable to take first place.  They had to take second due to a 3-point difference.  The two shed tears as they relayed their gratitude for each other.

Next was Jung In and Ahn Byung Min performing Girls' Generation's "Party."  They got 420 points, unable to take the first place spot.  Following was B1A4's Sandeul and Jo Sun Young who won two weeks ago!  They performed Jeon Ram Hee's "Memory's Etude," and succeeded in defending their crown with 429 points!  This makes it their third win.  As for the duo audience wanted to see again, Lee Suk Hoon's team was chosen.