Actor Kim Woo Bin suffered a knee injury on the set of his film "Twenty."

The injury was serious enough to halt filming on Aug. 24 and the actor was taken to the emergency room at Jungbuk Hospital in Jeonju. At the hospital he was examined for about an hour and his exam included an MRI scan of his left knee.

The scans showed that the ligaments and cartilage in his knee were damaged but no information was released as to the severity of his injury. Knee ligaments can be sprained or torn. Also, some part of the ligament can tear or the whole ligament can tear through completely, requiring surgery. His injury must not have been that severe, as he was not scheduled for surgery. But even minor knee injuries can affect a person's ability to walk properly and take months to heal.

Not only Kim Woo Bin did have to halt filming and he could not attend a press conference the next day that was hosted by the Jeonju Film Commission.

Kim Woo Bin is the latest in a series of k-celebs to sustain injuries on set. JYJ's Park Yoochun sustained a similar injury when he tore a shoulder ligament while filming an action scene in the drama "Three Days."

According C-JES Entertainment, Park Yoochun complained about pain for a week before going to the hospital. An MRI revealed a tear and he was told it would take about three months to heal.

Park Yoochun chose not to drop out of "Three Days" and the production company worked to adjust his filming schedule.

To recover and reduce complications, Kim Woo Bin will have to limit his movements and he must rest his injured knee. He will likely also face few months of recovery time.

"Twenty" is a film about three 20-something friends. Kim Woo Bin, who played bad boy Choi Do Young in "The Heirs," plays girl-crazy but unemployed Chi Ho. Jung So Min, who played the repentant heiress in "Big Man," will play So Min, a character that repeatedly breaks up with Chi Ho.

Junho plays Dong Woo, a young cartoonist, while Lee Yubi plays So Hee, a girl with a crush on Dong Woo. Kang Ha Neul plays college freshman Kyung Jae, a young man who tends to want what he can't have.

"Twenty" is scheduled to premiere in the first half of 2015. There is no way to know whether Kim Woo Bin's injury will delay the projected premiere date.