Oh My Girl returned to the old school days on the July 15 composer Park Shi Choon special�of 'Immortal Song'.

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In '60s school uniforms, Oh My Girl covered Baek Nan Ah's 68-year-old song "Sweet 18", which is a perfect song for the rookie girl group. Before performing on stage, Oh My Girl said, "It's a song released in 1949, but all our members knew it," remarking on the longevity of the song.



Spoilers Below:

The audience loved Oh My Girl's throwback to the old hit as well as their stage outfits, but it was married couple Yoo Sung Eun�and Bong Goo�who took the final win.

Original song from 1949: