The man who admitted to plotting to kidnap David Letterman's son, Harry, is back in prison. Montana cops caught up with Kelly A. Frank today in Northwest Montana. Frank escaped from Montana State Prison last Friday with another inmate, who is still on the run has been captured. Frank was arrested in 2005 on charges that he planned to kidnap Harry Letterman and his nanny and hold them for $5 million ransom. He would've been eligible for parole next month. Dumbass.