Terileptils were a space-faring reptilian species, well known for their great love of art and beauty, matched only by their great love of war. They served as the antagonists of the 1982 Doctor Who episode The Visitation

A small group of Terileptils arrived on Earth in 1666 during the Black Death and attempted to release a virus that would wipe out humanity and seize control of Earth themselves. This plan failed when The Fifth Doctor and his companions battled them in a bakery on London's Pudding Lane.

During this battle, a burning torch dropped and together with a overloaded Terileptil hand weapon resulted in causing The Great Fire of London which killed the Trileptiles and destroyed their augmented plague bacteria.