In his second outing titledThe Voyages of Doctor Dolittle, the maverick physician takes on a new assistant, Tommy Stubbins. The story is structured as a first person account given by Tommy, who is now a very old man. The boy who was the son of the village cobbler first meets Doctor Dolittle when he takes a hurt squirrel to the doctor for treatment. Tommy and the doctor quickly become friends, and the boy soon learns how to communicate with animals in their own languages. The remarkable talking parrot, Polynesia and other amazing creatures from the previous book also appear in this sequel. The mysterious disappearance of a friend of the doctor's called Luke the Hermit sets off a train of strange events. And Tommy finds himself accompanying the good doctor on an exciting, hazardous voyage to find Long Arrow, a native American and the son of Golden Arrow, who is reputed to be the greatest living naturalist in the world.

The kind hearted, quirky, animal rights activist Doctor Dolittle dominates the plot. His enduring humanitarian approach to the world around him, his desire for peaceful coexistence among all and his concern for the environment make him a memorable and endearing character. This as much an adventure story as a strong appeal for compassion towards the innumerable species that share our planet with us. There are shipwrecks, South American and Mediterranean locations, underwater explorations where they discover a giant sea snail and wonderful descriptions of land and sea.

Critics of Hugo Lofting's work point out that there are several passages which are now politically incorrect. However, readers would do well to remember that these books were written more than a hundred years ago, when attitudes to colonization and race were quite different.

In the dozen or so books featuring Doctor Dolittle, the author Hugo Lofting ensures that a wide variety of themes, locations and ideas are explored. The books were originally illustrated by the author himself, as he was a talented artist and naturalist himself.