While some actors need to lose or gain weight for a particular character, others wowed the viewers with their surprising disguise, dressing from male to female and vice versa.
With that, here's a rundown of iconic and newest gender-bender K-drama series that will surely give the audience a mood for some major laughs.
'The King's Affection'
Starting from the most recent Korean drama is "The King's Affection," starring Park Eun Bin, SF9 Rowoon, Nam Yoon Su, and more.
In the KBS historical drama, the "Hot Stove League" actress took on the role of crown prince Lee Hwi, who was disguised as her twin brother.
To conceal her true identity, she distances herself from others and even hides her emotions despite harboring a hidden affection towards her teacher Jung Ji Woon, who also comes from an aristocratic family.
"The King's Affection" premiered on October 11 and airs every Monday and Tuesday via KBS and Netflix.
The webtoon-based Kdrama "Yumi's Cells," which stars Kim Go Eun and Ahn Bo Byun, recently welcomed the character of GOT7's Jinyoung as Yoo Bobby.
In episode 8, the new character plays an interesting yet intriguing connection towards Yumi.
In one scene, the cells at Sepho village debate whether a man and a woman should be friends.
As one of Yumi's cells explained the pros and cons, she used Yoo Bobby to illustrate that the scenario would be different if he were a girl.
GOT7's Jinyoung looked unrecognizable yet stunningly gorgeous wearing a shoulder-length wig as he transformed himself into a girl.
IN CASE YOU MISSED: 'Yumi's Cells' Episode 8: Will GOT7's Jinyoung Ignite Romantic Crisis Between KIm Go Eun and Ahn Bo Hyun?
One of the iconic gender bender Kdrama is "Coffee Prince," with lead stars Gong Yoo and Yoon Eun Hye.
The duo portrayed coffee owner Choi Han Gyul, while Go Eun Chan, played by the "Princess Hours" actress, disguised herself as a man to be able to work at the coffee shop.
'Eulachacha Waikiki 2'
JTBC's rom-com "Eulachacha Waikiki 2" featured Lee Yi Kyung's versatility as an actor while entertaining the viewers with his hilarious character.
In some of the episodes, he transformed himself as a court lady.
'The Tale of Nokdu'
The 2019 Kdrama, "The Tale of Nokdu," illustrates a new twist on the gender-bender-themed series.
The historical rom-com featured the character of Jeon Nok Du a.k.a "Lady Kim," played by the South Korean heartthrob Jang Dong Yoon.
He transforms and cross-dresses to infiltrate a mysterious, windows-only village to find out his assassin.
To make ends meet, Kim Yun Hee, played by Park Min Young, pretends to be his brother and enters a men's only national exam for her to support her family after her father and younger brother died.
At the Sungkyunkwan University, she meets Lee Seon Joon, played by Park Yoo Chun who came from a wealthy family.