ELFs may remember Heechul and TRAX's Jungmo come together a few years ago as the project group 'M&D', which stood for 'Midnight & Dawn'.

Well, the project group may be having a comeback, as Jungmo tweeted a photo of himself and Heechul recording at the studio (complete with an Elsa background, once again showing Heechul's unending love for 'Frozen'). He wrote, "Midnight & Dawn...Ready?"

Heechul and Jungmo have put on various infamous performances together, including a rather famous open-mouthed kiss. In 2011, they had "Close Ur Mouth". The song may be an actual promoted track or just a rendition of a 'Frozen' OST, but stay tuned for more!