George Edward Challenger is a fictional character in a series of fantasy and science fiction stories by Sir Arthur Conan Doyle. Unlike Doyle's self-controlled, analytical character, Sherlock Holmes, Professor Challenger is an aggressive but virtuous figure.

Like Sherlock Holmes, Professor Challenger was based on a real person—in this case, two people: an explorer named Percy Fawcett, who was Doyle's friend; and a professor of physiology named William Rutherford, who had lectured at the University of Edinburgh while Conan Doyle studied medicine there.

George Edward Challenger, FRS, MD, DSc, is born in Largs, Ayrshire in 1863 and educated at Largs Academy before studying at the University of Edinburgh. Dr Challenger is appointed to an assistant position at the British Museum in 1892 and is promoted within a year to assistant keeper in the Comparative Anthropology Department. He holds a professorship in Zoology and is elected President of the Zoological Institute in London. Several of his inventions are successfully applied in industry and bring him additional income.

Edward Malone, the narrator of The Lost World, the 1912 novel in which Challenger first appears, describes his first meeting with the character:

His appearance made me gasp. I was prepared for something strange, but not for so overpowering a personality as this. It was his size, which took one's breath away – his size and his imposing presence. His head was enormous, the largest I have ever seen upon a human being. I am sure that his top hat, had I ventured to don it, would have slipped over me entirely and rested on my shoulders. He had the face and beard, which I associate with an Assyrian bull; the former florid, the latter so black as almost to have a suspicion of blue, spade-shaped and rippling down over his chest. The hair was peculiar, plastered down in front in a long, curving wisp over his massive forehead. The eyes were blue-grey under great black tufts, very clear, very critical, and very masterful. A huge spread of shoulders and a chest like a barrel were the other parts of him which appeared above the table, save for two enormous [hand]]s covered with long black hair. This and a bellowing, roaring, rumbling voice made up my first impression of the notorious Professor Challenger.

Challenger is a scientific jack-of-all-trades. Although considered by Malone's editor, Mr McArdle, to be "just a homicidal megalomaniac with a turn for science", his ingenuity can be counted upon to solve any problem or get out of any unsavoury situation; and be sure to offend and insult many people in the process. He is also seen as extremely vain by his colleagues: Edward Malone says that "he is convinced, of course, that he is destined for Westminster Abbey" (i.e. famous enough to be buried there), and later speculates that "in his fancy, may he see himself sometimes, gracing the vacant pedestal in Trafalgar Square". Challenger is, in many ways, rude, crude, and without social conscience or inhibition. Yet he is a man capable of great virtue and his love of his wife is all-encompassing.^{[citation needed]}

Challenger marries Jessica—'Jessie'—and the couple settles at 14 Enmore Gardens, Enmore Park, Kensington, London. After his adventures in South America, Challenger and his wife purchase The Briars, in Rotherfield, Sussex, as a second home. Later, following his wife's death from influenza, Challenger sells his London home and rents an apartment on the third floor in Victoria West Gardens, London. Challenger's friend and biographer, the journalist Edward 'Ted' Dunn Malone, marries Enid Challenger, the Professor's daughter, in the summer of 1927. Malone was born in Ireland and achieved some fame in rugby football at international level for Ireland before a career in journalism at the Daily Gazette. Enid Challenger is a freelance reporter at the same newspaper.

In July 1908, Malone joins Challenger, the 66-year-old Mr Summerlee (c. 1842–1925), Professor of Comparative Anatomy, and the explorer and mountaineer Lord John Roxton, third son of the Duke of Pomfret and then in his mid-forties, on an expedition to the Amazon Basin, where Challenger claims to have observed creatures from prehistory two years previously. On reaching the mouth of the Amazon River in Pará state, the expedition hires local guides and servants Mojo, José, Fernando, Gomez, Manuel and Zambo. From Manaus the expedition continues up-river to reach an unnamed tributary, which they follow by canoe until by late August the explorers arrive in the Guiana Highlands and the great plateau that is the Lost World. The expedition camps at the foot of the basalt cliffs of the mountain, which they name Maple White Land in honour of the plateau’s discoverer some four years earlier. The isolated plateau is home to numerous prehistoric animals, previously known only from the fossil record, including dinosaurs, pterosaurs, sauropterygians, Cenozoic megafauna, ichthyopterygians, and an early species of hominid. A group of indigenous people also occupy the plateau, and the explorers aid them to subjugate the predatory 'ape-men'. The expedition returns to London, bringing with them diamonds worth £200,000. Professors Challenger and Summerlee present their findings to the Zoological Institute on 7 November 1908 at the Queen's Hall, Regent Street, London. They claim to have discovered over 150 new species.