This concluding volume delves into prehistorical puzzles that begin with the Doctor's arrival on the lunar surface in Doctor Dolittle in the Moon. There he not only meets the Moon Man and intelligent plants, but learns how the moon came to be in the first place. In Doctor Dolittle's Return, he sets out to reveal all he learned on the moon, but is no sooner off to Africa to rescue his old friend, Mudface the turtle, the last living passenger of Noah's Ark. In Doctor Dolittle and the Secret Lake, we at last hear his fascinating tale of The Great Flood.