September 2025 is shaping up to be a packed month for K-drama lovers, with everything from gritty thrillers and political action to heartfelt romances and historical sagas. Whether you’re into con-artist capers, slow-burn friendships, or larger-than-life assassins, there’s something new to add to your watchlist this month. Here’s a roundup of the biggest Korean releases hitting OTT platforms in September.
Queen Mantis Release date: September 5, 2025 Where to watch: Netflix Cast: Go Hyun Jung, Jang Dong Yoon Episodes: 8 Jung Yi Shin isn’t your average mother — she’s a woman with a chilling past, accused of murdering five men two decades ago. Her estranged son Cha Su Yeol, a police officer, despises her but is forced to seek her help when a new killing mimics her methods. A tense mother-son dynamic unfolds against the backdrop of brutal crime.
2/7
Confidence Queen Release date: September 6, 2025 Where to watch: Prime Video Cast: Park Min Young, Park Hee Soon, Joo Jong Hyuk Episodes: 12 A remake of Japan’s Confidence Man JP, this drama follows three slick con artists who use brains, wit, and charm to swindle villains. With Park Min Young leading the trio as a genius strategist, expect clever schemes, high-stakes games, and a dash of humour.
3/7
Tempest Release date: September 10, 2025 Where to watch: Disney+ Cast: Jun Ji Hyun, Gang Dong Won, John Cho, Park Hae Joon, Kim Hae Sook, Yoo Jae Myung, Oh Jung Se Episodes: 9 Diplomacy meets espionage in this star-studded thriller. Jun Ji Hyun plays a top diplomat while Gang Dong Won takes on the role of a mysterious special agent. Their paths collide when a catastrophic attack threatens peace on the Korean Peninsula, forcing them to use their past experiences in a race against time.
4/7
You and Everything Else Release date: September 12, 2025 Where to watch: Netflix Cast: Kim Go Eun, Park Ji Hyun, Kim Gun Woo Episodes: 15 A moving story of friendship, jealousy, and mortality. Two childhood best friends take very different paths in life, but when one is diagnosed with terminal cancer at 42, she turns to the other to help plan her final days. Expect raw emotions, layered performances, and tear-jerking moments.
Crime Scene Zero Release date: September 23, 2025 Where to watch: Netflix Cast: Jang Jin, Park Ji Yoon, Jang Dong Min, Kim Ji Hoon, An Yujin (IVE) Episodes: 10 A unique unscripted format where participants play both suspects and detectives. With new crime scenes and surprise guests every episode, contestants must outwit each other to survive while unraveling mysteries. Perfect for fans of reality TV with a psychological twist.
6/7
The Murky Stream Release date: September 26, 2025 Where to watch: Disney+ Cast: Rowoon, Shin Ye Eun, Park Seo Ham Episodes: 9 Set in the Joseon dynasty, this period drama explores survival amid corruption. A gangster, a merchant, and an idealist bureaucrat cross paths as the once-pristine Gyeonggang River turns into a symbol of decay. With political intrigue and personal struggles, it promises to be a gripping historical saga.
7/7
Mantis Release date: September 26, 2025 Where to watch: Netflix Cast: Im Siwan, Park Gyu Young, Jo Woo Jin From the universe of Kill Boksoon comes another stylish assassin drama. Im Siwan plays Mantis, a top hitman forced to navigate betrayal, rivalries, and survival outside the notorious MK Enterprise. With high-octane action and layered character conflicts, this is one for fans of dark thrillers.