SEE ALSO: Seoul Philharmonic Orchestra reveals dramatic MV for Red Velvet's 'Psycho'

Wendy, Joy, and Seulgi covered Baeho's classic hit "Hello". Before their performance, the three expressed how they felt when they first found out that the trio would be appearing on 'Immortal Song', saying, "We were surprised when we found out we were coming on 'Immortal Song', and we wondered if it was okay for us to appear. It feels different for us because it's the first time the three of us are singing together like this."

Their RnB cover put groovy, ballad elements into the old-school song as well, and the Red Velvet members definitely showed the audience something unexpected. It was Park Ki Young (Highlight for Spoilers) who took the final win.