Believe it or not, many of the popular actors that you know and love dearly weren't so popular or even known back in the day.

Your favorites like Song Joong Ki and Lee Min Ho all started out from humble beginnings, starting out with minor, smaller, supporting roles for the small screen. Not every role these guys took on was successful; there was bound to be failure along the way. Unless you're a big fan of the actor, you may not even recognize some of these 'obscure' roles!

But you already know the deal--their hard work and talent eventually paid off and these actors moved onto bigger and better things, making their grand breakthrough with memorable, impressive characters that we will all love for a long time!

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Song Joong Ki

Before he was in 'Descendants of the Sun' and other breakthrough roles, Song Joong Ki had tried to make a name of himself as an extra in dramas like 'Get Karl! Oh Soo-jung.' In 'Get Karl!' Song Joong Ki only appeared briefly as a reporter. Then he became more widely known through 'Sungkyunkwan Scandal,' making all the ladies' hearts flutter as the handsome scholar Goo Yong Ha! 

Park Seo Joon

This flower boy (man?) started his acting career in Bang Yong Guk's MV for "I Remember". Since then, he turned popular as one of the main characters for 'Dream High 2' and his recent breakthrough as the slightly apathetic Chief Editor of 'The Most' on 'She Was Pretty.' 

Kim Soo Hyun

Remember the chic, cold alien Do Min Joon on 'You Who Came From the Stars'? Of course you do! It was probably Kim Soo Hyun's biggest role in his over decade long career. But before Do Min Joon, there was the Kim Soo Hyun of 'Kimchi Cheese Smile'...and a couple of roles in musical theater.

Lee Min Ho

Lee Min Ho had begun with a very insignificant role in coming-of-age drama called 'Sharp.' He wasn't recognized until his leading character in 'Boys Over Flowers' as the petulant, immature Goo Jun Pyo. I guess girls really like those types?

Park Bo Gum

Park Bo Gum actually started off in film and then moved onto dramas. He played a supporting role as Kim Ha Neul's brother in 'Blind.' His big break came in 'Reply 1988,' the hit series which made fans love him even more and people jump on the Park Bo Gum bandwagon.

Ryu Joon Yeol

You may not have know who Ryu Joon Yeol was when he played a rookie producer in the popular drama 'Producer.' It's not his smallest or most minor role, but few people really knew who he was back then. It was only until his role in 'Reply 1988' as Kim Jung Hwan that he started garnering attention. Viewers couldn't help fall for those stoic charms! 

Seo Kang Jun

Lee Jong Suk

Before you knew Lee Jong Suk through his roles in 'Secret Garden' and 'I Can Hear Your Voice,' you might have seen him in 'Prosecutor Princess.'  He doesn't have a big role in that one, just a worker at the prosecution office, but he hit it big pretty soon after!