Q.E.D. is a 1982 adventure television series set in Edwardian England, starring Sam Waterston as Professor Quentin Everett Deverill. The Professor was a scientific detective in the mold of Sherlock Holmes, and the series had a smattering of what would later be called steampunk. In the show, the lead character was known primarily by his initials, Q.E.D; the reference here is that Q.E.D. usually stands for quod erat demonstrandum, a statement signalling the end of a proof.However, characters would sometimes state the initials to represent "quite easily done".

The series was broadcast during March and April, 1982 on the CBS television network in the United States, and by a variety of ITV companies in the United Kingdom.