Oliver's Divine Delivery Theory is put to the test as the Postables take on another mailbox mystery. On the set of a Denver-based commercial, a battered package is found in a prop mailbox. The Postables discover the package held a bucket list, which apparently belonged to someone who is nearing the end of his or her life.
Before Oliver has a chance to fully investigate this mystery, Shane convinces him to take a break from work and join Joe on a camping trip. Norma and Rita travel out-of-state in an attempt to deliver the lost package. Witness the next exciting adventure of the Postables in Signed, Sealed, Delivered: Lost Without You.