IU's Best Deep Album Cuts: 'The Shower,' '23' & More

Han Myung-Gu/WireImage
IU attends the press conference for KBS drama 'Produca' at The RAUM on May 11, 2015 in Seoul, South Korea.

Want to dive deep into the K-pop superstar's back catalog? Here are the 10 songs to start with.

IU has made her return to the musical scene with a new EP Chat-Shire which lands at No. 19 on Billboard's Heatseekers Albums chart, her first appearance on the chart, and No. 4 on World Albums this week, tying her best rank ever on the chart. The release is yet another must-hear from the singer's remarkably strong discography.

Every IU release is cause for celebration on the K-pop scene and the charts always immediately feel the young singer's impact -- from her singles and the deep cuts. Wrap your head around the hype for Korea's musical sweetheart with 10 essential non-singles from her albums that, for the record, are worth full listens -- a phenomenon rare in K-pop.

"Bad Day"
From: Modern Times (2013)

A stunning ballad that begins as a hushed, piano-and-string croon and climaxes into an impassioned belt session where IU layers her voice and harmonizes with herself for a breathtaking vocal performance only to cadence back to the hushed opening. It's almost like the sonic equivalent of consciously arguing with yourself about why you're having a "bad day," only to end up at the same, sullen place you began.

"Feel So Good"
From: Lost and Found (2008)

Even on her debut EP, IU was showing she had great material past the singles. "Feel So Good" is an R&B-tinged groove that highlights then 15-year-old's honeyed vocals over a knocking beat.

"23"
From: Chat-Shire (2015)

With production remarkably similar to Britney Spears' "Gimme More," IU tried on a dark synth-pop sound with "23," a song recorded for Korean TV drama The Producers where she played an icy pop diva. The track was a bonus cut on the physical version of Chat-Shire. While she typically avoids chart-topping trends, it makes us wonder what would happen if IU went full-on trendy pop a la Taylor Swift and 1989BrIUtney Spears, anyone? 

"Secret"
From: Last Fantasy (2011)

A sweeping, classical-leaning song that sounds like it could soundtrack any blockbuster film. Last Fantasy's opening track set the cinematic feel of the album with featured choir and flute sounds. 

"Love Attack"
From: IU...IM (2009)

The peppy opener from her 2009 EP proves why it's nearly impossible not to fall in love with IU's charms. "Love Attack" captures her youthful energy with a frenetic electro-pop production.

"Pierrot Laughs at Us"
From: A Flower Bookmark (2014)

The most ambitious tune she tackled in her 2014 covers EP, the disco-tinged tune further proves IU's diversity. Listen up for the wonky key change where our girl comes off like sweet-singing robot.

"Havana"
From: Modern Times (2013)

There are so many standouts on Modern Times, it's really hard to limit the picks of top tracks. But the Latin-jazz sound on "Havana" stands out for its natural fit on IU and proves how the singer is only limited by her own creativity. Don't miss the Afro-Cuban breakdown on the bridge.

"The Shower"
From: Chat-Shire (2015)

A gorgeous standout from Chat-Shire sees IU looking back to the classical sound she owned on Last Fantasy , but this time with a melodica twist.

"This Is Not What I Thought"
From: Real (2010)

A song that mixes electro-pop production with burst of classical music that continue to swirl together over IU's adolescent coos about reuniting with an ex-lover.

"Scary Fairy Tale"
From: Real+ (2011)

A song that takes its name quite literally, crunchy beats are mixed with classical production that wouldn't be out of place in a Tim Burton film. Another one of IU's most creative and ambitious moments.