Seung-heon at the Osaka Dome. Lee performed at American singer Christina Aguilera's Seoul concert on June 24 as part of her Back to Basics Tour. Aguilera reportedly viewed video clips sent in by Korean artists, as she wanted to choose the best. The artists were viewed for their dancing and singing abilities, as well as album sales. Ivy performed as the opening act for the first concert on June 23, while Lee performed on the second day. In mid-July 2007, Lee release his third album Explore, which was in the R&B/dance style of his previous albums. He had composeed nine songs and the album debuted at number three on the chart. Although he intended to release it in the U.S., via CJ Music and CJ Entertainment's global network, it was released in Korea instead. 2008–2011: Mini album and military service Lee's third album M Rizing, sold over 30,000 copies in 2008. Lee's first single from the album was call Stomp, where it was number onefor two consecutive days on an online chart. His second single, “The M Style” was also quite popular as well, climbing up the charts just as quickly. Though his songs managed to chart well, the album sales were not as strong as its two predecessors, with the album dropping off the Korean Monthly Chart rather quickly. Lee released his first mini-album, The Sentimental Reason in February 2008 to coincide with Valentine's Day and White Day. Giving only a limited 13,000 copies, it sold out in less than a month. The mini-album was successful enough for Lee to promote it with two singles, "Just One More Night" and "Believe In Love". In June 2009, Lee made a comeback with mini album, Minnovation. He collaborated with American producer Outsidaz on title track, "Minnovation", which is infused with electronica and hip hop beats. In January 2010, it was reported that Lee was in a serious car accident on Christmas Eve, in which he sustained some serious injuries. He then held M′s Suite Room concert in February. On February 25, 2010, Lee enlisted for 24 months of mandatory military service, the last Shinhwa members to do so. He completed four weeks of basic training followed by non-active duty as a public service officer at Seoul Station. He was discharged on March 2, 2012. Shinhwa Company On July 1, 2011, Lee became co-CEO, along with Eric Mun, of Shinhwa Company, a