The illustrations are rich in blues and purples and greens, a palate that seems appropriate for a bedtime story, and full of details that give the characters personality and give the reader something to study.  The rhyming text describes a variety of troubles the Goodnight Train encounters on its journey which threaten to wake the sleepers aboard, but each challenge is met by the crew, with the refrain of, “Chugga! Chugga! Shhhhhhh! Shhhhhhh!” signaling that calm has once again been restored, and the sleepers are once again slumbering peacefully.