Money Today writes that around 2013 he was active as a dancer for the singer Sunmi. Sunmi says he has been her partner since her first solo song, “24 Hours.” In 2017, he entered the preliminary round of the Supermodel contest.
The breakthrough yearThe year he turned 27, he took the stage with Sunmi at Waterbomb 2018, and a fancam video drew attention and made his name known.
In 2019, he shot a Buckaroo pictorial with Sunmi. In 2020, he appeared in MBN’s Uri Dasi Saranghal Su Isseulkka 3 as an acquaintance of the actor Hyun Woo. In 2021, he appeared in Netflix’s Single’s Inferno season 1 as a cast member who joined partway through.
In March 2022, he launched the fashion brand 5/2Bright and appeared in Mnet’s Be Mbitious. He took part in Sunmi’s stage at Waterbomb 2022 Seoul and appeared on the judging panel of JTBC’s Hidden Singer 7.
The year he turned 32, he appeared in Netflix’s Physical: 100. In February that year, he donated 10 million won for emergency relief for earthquake-affected children.
In January 2024, he announced his retirement as a dancer and began working as an actor. He appeared on King of Mask Singer, and in October the short-form drama Haeyaman Haneun Share House was released.
In 2025, he appeared in Wavve and Dramax’s No Mercy. In September he revealed he was being treated for leukemia, and he said he was declared cured on Dec. 22. In July 2026, he took the stage with Sunmi again at Waterbomb Seoul 2026.
Cha Hyun-seung (born May 2, 1991) was active as a dancer for the singer Sunmi around 2013, the year he turned 22, and became known on Jul 21, 2018, the year he turned 27, when a fancam video of his Waterbomb 2018 stage with Sunmi drew attention. In 2023, the year he turned 32, he appeared in Netflix’s Physical: 100.
Ages are by calendar year (the year minus the birth year), birthdays aside.
Money Today writes that he was active as Sunmi’s dancer in 2013. Sunmi says he has been her partner since “24 Hours.”
Source 01 · Money Today (Korean) · Shares his illness story · opens in a new tabSource 02 · Gonggam News (Korean) · Appears on Hidden Singer 7 · opens in a new tabSource 06 · My Daily (Korean) · Sunmi showcase · opens in a new tab The articles give no month or day. The timing follows Money Today.Showed a talent in the preliminary round at SBS Prism Tower in Sangam-dong, Seoul.
Source 03 · Newsen (Korean) · Supermodel contest preliminary · opens in a new tabA fancam video of the stage with Sunmi at the Jamsil Sports Complex drew attention. Ten Asia writes that the video made his name known at once.
Sunmi said she did not know the Waterbomb video would draw attention. She also said Cha Hyun-seung has been her partner since “24 Hours.”
Source 05 · Top Star News (Korean) · Sunmi showcase · opens in a new tabSource 06 · My Daily (Korean) · Sunmi showcase · opens in a new tabThe pictorial shows them in denim clothing in poses like a couple dancing.
Source 08 · Money Today (Korean) · Sunmi x Cha Hyun-seung Buckaroo pictorial · opens in a new tabAppeared as an acquaintance of the actor Hyun Woo, introduced as a model and dancer who works out with him.
Source 26 · Sports Chosun (Korean) · Uri Dasi Saranghal Su Isseulkka 3 · opens in a new tabJoined the cast partway through. My Daily wrote in January 2022 that he had already drawn attention before the show for his 2018 “Sunmi Waterbomb” stage.
Source 09 · Top Star News (Korean) · Single’s Inferno male wildcard · opens in a new tabSource 10 · My Daily (Korean) · Single’s Inferno, Cha Hyun-seung · opens in a new tab The articles give no release date for the episode he joined, so only the month is shown.Launched a clothing brand with the multichannel network Mango Play. The brand name combines his birthday and the character “hyun,” meaning bright.
Source 25 · Fashionbiz (Korean) · 5/2Bright launch · opens in a new tabApplied as a solo dancer after Single’s Inferno and appeared in the first episode. He was picked by No. 9 in the target selection before entering.
Source 11 · News1 (Korean) · Be Mbitious premiere · opens in a new tabTook part in Sunmi’s stage at the show at the Jamsil Sports Complex.
Source 12 · Top Star News (Korean) · Cheering Sunmi’s comeback · opens in a new tabEpisodes 1 and 2 were released, and the first quest was a match between Cha Hyun-seung and the farmer Kim Kyung-jin.
Source 13 · Star News (Korean) · Physical: 100 first release · opens in a new tabThe Korean Committee for UNICEF said he donated through the committee.
Source 14 · Star News (Korean) · Earthquake relief donation · opens in a new tabPosted it on his YouTube channel, announcing his acting debut.
Source 15 · Star News (Korean) · Announces retirement as a dancer · opens in a new tab The articles give no exact date, so only the month is shown.Posted a message on social media thanking Sunmi for the stages they shared over 10 years. Star News reported it as a retirement announcement and an acting debut.
Source 15 · Star News (Korean) · Announces retirement as a dancer · opens in a new tabFaced the Hot Sauna in the first round and his identity was revealed.
Source 16 · Star News (Korean) · King of Mask Singer · opens in a new tabAppeared as Yu-seung, the aide of Ma Seok-gu, played by Ji Seung-hyun.
Source 18 · bnt News (Korean) · No Mercy premiere · opens in a new tabSource 19 · Newsen (Korean) · No Mercy, as Yu-seung · opens in a new tabSaid on social media that he had been rushed to the emergency room in early June and was being treated.
Source 20 · Sports Chosun (Korean) · Reveals his illness · opens in a new tabSource 01 · Money Today (Korean) · Shares his illness story · opens in a new tabSaid on Instagram that he was declared cured on Dec. 22.
Source 21 · Segye Ilbo (Korean) · Declared cured · opens in a new tabPosted a photo with Ma Dong-seok on social media with a caption saying it was day 1 of boxing.
Source 22 · Newsis (Korean) · Boxing with Ma Dong-seok · opens in a new tabTook the stage with Sunmi at the KINTEX outdoor Global Stage in Goyang, Gyeonggi. It was his first stage with her since he was declared cured.
Source 23 · Maeil Business (Korean) · Waterbomb Seoul 2026 · opens in a new tabSource 24 · Xports News (Korean) · Waterbomb reunion · opens in a new tabEND OF SELECTED RECORDSSelected records, 2013–2026 · not a complete list of work. “Key moment” is an editorial label, not a measure of success.
What did they do, and at what age?
AgeTrail lines up the key moments of a life by age.
Debut and breakthrough are marked separately, and every record has a source.
Arts · South Korea
May 2, 1991 —
Ages are counted from the birth year 1991: the year of the event minus 1991, birthdays aside. “Key moment” labels and the connecting story are AgeTrail's editorial reading.
Fact-checked: 2026.09.30 · An independent archive, not affiliated with the person or their agency.