Kvolution

✨ Lee Ji Eun

2008–09: Career beginnings

IU performing "Boo" on October 29, 2009.

After spending 10 months as a trainee, IU released "Lost Child" (Korean: 미아) as her first single. She performed the song live for the first time on the music program, M! Countdown, on September 18, 2008, making it her debut performance as a professional singer. Regarding the performance, IU recalled the crowd had hurled insults at her and though she felt discouraged by it, she now considers it a beneficial experience. "Lost Child" is the lead single from her debut extended play Lost and Found, which was released on September 24, 2008. For the album, IU was awarded the "Rookie of the Month" by South Korea's Ministry of Culture, Sports and Tourism in November 2008. However, the album did not do well commercially. During an interview in 2011, IU said, "My first album failed, but I'm grateful for that. If I had become successful as soon as I made my debut, I wouldn't appreciate my staff members and the popularity that I'm enjoying now."

On April 23, 2009, IU launched her first studio album, Growing Up, with the lead promotional single, "Boo". She began her album promotion the next day, performing "Boo" on KBS2'sMusic Bank. The song was noted for its stark contrast in musical style to "Lost Child", which was described as a "heavy" and "dark" ballad compared to the 1980s "retro sound" of "Boo".Deemed as a "strategic" transformation, the dance choreography, stage costume and hairstyle shown in live performances were used to emphasize her youthfulness and project a "cute" image. Although it drew a favorable response from the public, IU, who was fifteen years old at the time, admitted that the image made her feel awkward. The song was nominated as a number-one contender on the popular music program, Inkigayo. Along with several songs fromLost and Found, "You Know" (Korean: 있잖 아) was also featured in Growing Up; a newrock-style arrangement of the song was released as the follow-up single to "Boo".

Towards the end of 2009, IU released her second extended play, IU...IM. She began promoting its lead single, "Marshmallow" (Korean: 마쉬멜로우), on music programs across the three major television networks from November 13, 2009. The song was described as "saccharine" with a style that was a hybrid of the rock-and-roll of the 1960s and "French pop".Recalling the performances, IU stated on a 2013 episode ofHappy Together that she disliked having to wear the girlish costumes and hairstyle fashioned for the song promotions. The performances were well-received and were once again labelled "cute", reminiscent of reviews for "Boo".

In addition to her album releases in 2009, IU participated in her first soundtracks via two MBCtelevision dramas, Strike Love(Korean: 2009 외인구단) andQueen Seondeok (Korean: 선덕여왕). She also collaborated with artists such as Mighty Mouth and The Three Views on their albums. As her popularity began to rise, IU made more frequent appearances on variety shows, performing on Star Golden Bell,Kim Jung-eun's Chocolate andYou Hee-yeol's Sketchbook. Her acoustic covers of other artists' songs such as Girls' Generation's "Gee", Super Junior's "Sorry, Sorry", and Big Bang's "Lies" (Korean: 거짓말) featured in these live performances gained tremendous interest online.In late 2009, she became a TV presenter for the first time, hosting a weekly music chart show on Gom TV, while appearing as a fixed guest on multiple radio programs such as Kiss the Radio, Volume Up,MBC Standard FM's Starry Night and MBC FM4U's Best Friend Radio.

2010–11: Rising popularity and acting debut

On June 3, 2010, IU released "Nagging" (Korean: 잔소리), a duet which she recorded with2AM's Lim Seul-ong. The single debuted at twelve on the Gaon Digital Chart and shot up to number-one position the following week, where it remained for three weeks. Written by Kim Eanaand composed by Lee Min-soo, the pop ballad duet was used as one of the theme songs for the second seasonof the variety show, We Got Married. The song was popular on music programs, where it won the Mutizen award on Inkigayo and was placed first on Music Bank.Soon after, IU released "Because I'm a Woman" (Korean: 여자라서), one of the theme songs of MBC's historical period drama, Road No. 1 (Korean: 로드 넘버원). The song peaked at number six on the Gaon Digital Chart. IU's collaboration withSung Si-kyung on "It's You" (Korean: 그대네요) for his album, The First, debuted at number one on the Gaon Digital Chart.