A Mary Sue is a type of fictional character, usually a young woman, who is portrayed as unrealistically free of weaknesses or character flaws.[1] The term "Mary Sue" is often applied pejoratively to strong female heroines considered to be unrealistically capable, both in fan fiction and in commercially published fiction.
The character Mary Sue initially appeared in Paula Smith's 1973 parody short story "A Trekkie's Tale". In that story, Mary Sue symbolizes the idealized characters widespread in Star Trek fan fiction. These were often depicted as beautiful young women possessing special abilities or physical traits, universally beloved by the more established characters, and playing a central role in the story despite not appearing in the source material.[2]
Mary Sue stories are often written by adolescent authors, primarily young women, and may represent the author's self-insertion into the story. Less commonly, a male character with similar traits may be labeled a "Gary Stu" or "Marty Stu".