Yunho/U-Know has been busy filming the drama Heading to the Ground, which requires him to do some stunt work in addition to acting and looking hot on screen. For one particular stunt scene, two mattresses were placed at the bottom of a pool of water. Yunho was then asked to throw himself into the water, a scene that took five hours (as a well as a toll on his body) to film. The cast and crew members on set were impressed with Yunho's first attempt at a stunt act. He showed a lot of enthusiasm for the stunt production despite the intense work it took to film those scenes. Teasers for Heading to the Ground were recently released. The drama is scheduled to start airing on September 9th.