Before starring in the blockbuster Jumong, Song Il-Kook headlined Oasis, a thrilling, three-episode Korean TV drama series set in the early 1940s during the Japanese occupation of Korea. Fleeing an arranged marriage to a man she doesn't love, In-hee (Jang Shin-Young) meets Gi-hyun (Song Il-Kook, Jumong), an aspiring musician whose most prized possession is his late father's saxophone. In-hee and Gi-hyun cross paths over the years and slowly fall in love. In-hee ends up in the radio business working for Young-jin (Lee Jung-Gil, Boys Over Flowers), a Korean national who supports the Japanese government in its occupation of Korea. As Gi-hyun's musical career begins to take off, he discovers that Young-jin is the same man who murdered his father many years before. As the tension builds, Gi-hyun is suspiciously sent to work hard labor at a coal mine in Japan. Upon the Japanese defeat in World War II, Gi-hyun returns home, full of revenge, to find his life turned upside down.