Roy Kim revealed his new song "Spring Spring Spring" for the first time today.

Roy Kim held a surprise guerrilla concert in Namsan. He had posted on his Twitter, "See you here on April 21 at 3PM!"

The guerrilla concert had been held upon Roy Kim's request that he wants to let his fans hear his new song first before its release. At the concert site were not only his fans but also other visitors wanting to join, and total of about 4,000 audience members gathered.

Roy Kim sang his hit songs from Super Star K4 as well, including "Volcano", "In the Rain", "Becoming Dust", "I Need Healing", "Whistle" and more. He also performed Jason Mraz's "Beautiful Mess."

Roy Kim's self-written song "Spring Spring Spring" will be released tomorrow.

Photo Credit: CJ