The 'King of the Hallyu Wave', Bae Yong Joon, made a surprise 'voice appearance' on SBS's "Strong Heart"! On June 7th, Kim Hyun Joong made a guest appearance and revealed his close relationship with the CEO of his agency, Bae Yong Joon. He stated, "A while ago, I've heard that Yong Joong hyung went to Busan by himself so I went right away and stayed with him." The singer also called Bae Yong Joong during filming, which he fortunately answered. Reportedly, Bae Yong Joon praised Hyun Joong and expressed his deep fondness for the star. He also joked around by saying, "I want to see Hyun Joong being hit by the wind [as punishment for telling a 'weak' story]." It's said that Bae Yong Joon lived up to his reputation as a 'man of gentle charisma' by answering every cast member's question. The full episode is set to air on June 7th, so check back with allkpop for more updates! Source: Star News via Nate