Huh Gak will collaborate with an artist for his upcoming comeback single.

A Cube Entertainment revealed a teaser image on October 7th which shows the backview of Huh Gak together with a male artist along with a message,"Huh Gak X WHO? 'Up All Night' Digital Single 2015.10.14 00:00".

Huh Gak collaborated with A Pink's Eunji, Simon D, Jung In in previous hits so many people are very looking forward to his partner this time.

Who do think is Huh Gak's mysterious partner?