In the year 241, twelve-year-old Lina trades jobs on Assignment Day to be a Messenger to run to new places in her decaying but beloved city, perhaps even to glimpse Unknown Regions.

"Iris is the most colorful goddess girl at Mount Olympus Academy. In fact, her hair and delicate wings can change color according to her mood! When Principal Zeus entrusts her with the job of fetching some magic water, Iris is tickled pink--until she realizes she'll have to get the water from the gray, gloomy River Styx in the Underworld! And when Iris figures out how to create magical rainbow slides that will allow her to travel from Mount Olympus...

Calvin Curbhopper, a bicycle messenger, makes his way through the city in all kinds of conditions to make sure that his messages get delivered on time.

Soon after Victorian messenger Barnaby Grimes is attacked by a huge beast while crossing London's rooftops, he becomes entangled in a mystery involving patent medicine, impoverished patients, and very expensive furs.

Sixteen-year-old Heller Highland, who is living with his grandparents while his parents are away, burns rubber across Manhattan delivering bad news by bicycle, and as a summer heat wave melts the city, he is struck by first love.

Barnaby Grimes is pitted against an army of Victorian-era zombies. The funeral of a master criminal brings a dozen squabbling gangs together for a moment of peace, but when Barnaby shortcuts through the graveyard and sees the body rise from the earth, a terrifying mystery is born.

"In this tale set in the ancient Inka empire, Little Chaski has a big job: he is the Inka King's newest royal messenger. But on his first day things quickly start to go awry. Will Little Chaski be able to deliver the royal message on time?"--

"Amberground is locked in darkness. A man-made star casts only a dim light over the land. The pitch-black wilderness is infested with Gaichuu--colossal insects with metal exoskeletons. The Gaichuu make travel between the cities of Amberground extremely dangerous. But thankfully the Letter Bees, a brave corps of messengers, risk their lives in order to keep the hearts of Amberground connected. Gauche Suede is on his last delivery before a big...