|Signed Sealed Delivered: A dedicated quartet of civil servants in the Dead Letter Office of the U.S. Postal System who transform themselves into an elite team of lost-mail
detectives. Their determination to deliver the seemingly undeliverable takes them out of the post office into an unpredictable world where letters and packages from the past
save lives, solve crimes, reunite old loves, and change futures by arriving late, but always miraculously on time.