Chakra disbanded in 2004, and Jung pursued acting full-time. After undergoing 11 unsuccessful auditions that year, she said she began doubting her decision to become an actress. In 2005, she gained recognition in the cult vampire sitcom "Hello Franceska", then made her breakthrough in the romantic comedy "My Name Is Kim Sam-soon". The series was a massive success with average ratings of over 37%, and 50.5% for the finale. Jung was praised for her portrayal of a fragile but good-natured character who fights for the hero's love, and eventually became one of the few successful singer-turned-actresses in the country.