Trilogy

A trilogy (from Greek τρι- , "three" and -λογία -logia, "discourse") is a set of three works of art that are connected, and that can be seen either as a single work or as three individual works. They are commonly found in literature, film, or video games. Three-part works that are considered components of a larger work also exist, such as the triptych or the three-movement sonata, but they are not commonly referred to with the term "trilogy."

Most trilogies are works of fiction involving the same characters or setting, such as The Deptford Trilogy of novels by Robertson Davies and The Apu Trilogy of films by Satyajit Ray. Others are connected only by theme: for example, each film of Krzysztof Kieślowski's Three Colors trilogy explores one of the political ideals of the French Republic (liberty, equality, fraternity) and each novel in Paul Auster's The New York Trilogy uses formats from detective fiction to explore existential questions. Trilogies can also be connected in less obvious ways, such as The Nova Trilogy of novels by William S. Burroughs, each written using cut-up technique.

The term is less often applied to music, such as the Berlin Trilogy of David Bowie, linked together by their musical sound and lyrical themes, and that part of them was recorded in Berlin, Germany. Also in music, Adele has been quoted as saying that she "believes in trilogies", when asked if her fourth studio album will be titled after her age at the time of its writing. She considers her first three albums, 19, 21, and 25, part of a trilogy and will not name her fourth album accordingly.

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