The Postables find themselves on the case of Randilynn Amidon, a U.S. soldier being held captive in Afghanistan, who aids a truck driver by delivering his daughter's child. The driver, Asad, helps to deliver an envelope for Randilynn. The envelope is received and being held as classified by government officials. The Postables – Oliver, Rita, Norman and Shane – are all in attendance at an emergency Senate committee hearing, declaring they have information regarding the letter and could help in Randilynn's rescue. It is now up to the Postables to decode the cryptic clues in the letter. They soon discover that the clues refer to personal stories, Bible verses, and patriotic song lyrics to reveal her current plan to escape. While all this is going on, Rita competes for the National Miss Special Delivery title in Washington, D.C.
