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In the romantic comedy series "Do Do Sol Sol La La Sol" (2020), Lee Jae-wook portrayed the lead character Sun Woo-joon, a mysterious and introverted pianist who crosses paths with an optimistic pianist, Gu Ra-ra (played by Go Ara). This role marked Lee Jae-wook's first leading role in a television drama, showcasing his acting range and solidifying his status as a rising star in the Korean entertainment industry.