Jang Hyun-seung more commonly known as Hyun-seung, is a South Korean idol singer and dancer. He is best known as the lead vocalist of the boy band Beast, under the label Cube Entertainment. With Beast, he has released singles and albums in both Korean and Japanese. Beast won the Artist of the Year award at the Melon Music Awards in 2011.
Hyun-seung is also one half of the duo Trouble Maker with Cube labelmate HyunA. In December 2011, the duo released their debut mini-album with the lead single, "Trouble Maker", which won the triple crown on M.net M! Countdown.