Shin Hye Sung debuted as the lead singer for the popular Korean boyband Shinhwa. He auditioned in America and became the first member to be part of the group. Although Shinhwa didn't disband, He took part in the side-project S, along with his good friends Kang Ta and Lee Ji Hoon. He became the second member, after Min Woo, to release a solo album.

Hyesung was the second member in Shinhwa to release solo albums, the first being Lee Minwoo. Although he had wanted to go into R&B like Lee did, he chose to sing ballads as he did not want to rival his friend. He released his first solo album entitled Love of May in 2005. This album ranked number one on the HMV pre-order sales chart in Japan in February 2005, with 80,000 copies sold.