D.O. is the 5th member to give fans clues about EXO's Japanese comeback with their 1st full album, 'Countdown'.

While there isn't much information available about 'Countdown', D.O's teaser clip depicts a mixture between a futuristic and a retro vibe, with the idol sitting in a field of video film. Who do you think the 6th member will be?

You can visit EXO's special 'Countdown' website to see their mysterious code, here.