BTOB tried and failed to surprise their youngest member Sung Jae on the set of Who Are You - School 2015.

The group uploaded a video through Naver Star Cast of their preparation to surprise Sung Jae on June 15. With Sung Jae's drama Who Are You - School 2015 coming to an end, the other BTOB members wanted to give him their support with his busy schedule.

BTOB split into two teams, competing to see who could buy Sung Jae the best snack. Team Hyun Sik, Il Hoon, and Peniel purchased ribs and Sung Jae's favorite yogurt while team Chang Sub, Min Hyuk, and Eun Kwang bought some jelly snacks and drinks. Of course, the boys also bought some snacks for themselves.

Although the members tried to sneakily hide around the set Sung Jae spotted them instantly. Unfortunately, their plan to surprise him failed as Sung Jae said, "I heard that you guys were coming at least eight time today."

Still, Sung Jae was happy to eat and talk with his fellow members. He also picked the yogurt as his favorite snack, making Hyun Sik, Il Hoon, and Peniel the winners.

BTOB not only treated Sung Jae to surprise snacks but also prepared pizza for the show's staff.

While Sung Jae has finished filming for Who Are You - School 2015, BTOB are currently preparing for their next comeback. They are set to return around the end of June with a new style.