Paula Zahn‘s new show on Investigation Discovery has been greenlit for a second season after debuting as the highest rated series in the network’s history.

While only half of the first season has aired, the network announced that “On The Case with Paula Zahn” will return in 2010. So far, it’s averaging 402,000 total viewers each week.

Network president Henry Schleiff called Zahn’s show a “brand defining series for ID.”

TVNewser sat down with Zahn earlier this fall for an interview to discuss the program and her career.