The ship Beagle sets sail from England in 1831 to make a voyage around the world which will change history. On board are Charles Darwin, a 22 year old naturalist, and 15 year old cabin boy Syms Covington who will work for Darwin hunting animals, dissecting and labelling them. Both will go into the jungle, confronting earthquakes and volcanic erruptions, encountering animals and plants hitherto unknown, and they will begin to formulate the theory of evolution.