<P> "A" is a fictional character created in 2006 by author Sara Shepard . It is a character of both Pretty Little Liars' books and television series, and primarily appears as a stalker and the main antagonist of the stories . "A" is one of the main characters of the stories, appearing anonymously in the majority of the episodes and books . </P> <P> The villain has already had many portrayals . Its basic occupation is to pursue and threaten the four protagonists of the stories . Thus, many identities have been revealed to be "A". "A" has a specific and unhealthy way of dealing with the protagonists; it often calls them as "bitches", "dolls" and "liars". Its handling and acts of terrorism caused great psychological and emotional damage to the protagonists, even leading them to be hospitalized . </P> <P> After the revelation of Mona Vanderwaal as the first and original "A", she began receiving visits from someone, known as Red Coat, who offered her a partnership and together they built up the "A-Team". The team had many members but disbanded after the season three finale and Big A began working with a single ally . The identity of the second "A", Red Coat, and the leader of the "A-Team" was revealed to be CeCe Drake, while her ally that donned the Black Widow and other Red Coat disguise was revealed to be Sara Harvey . Five years later, a new mysterious entity arises and begins using Emojis to communicate but later baptizes themselves as "A.D.", while the Liars refer to the anonymous figure as Uber A. Then, in the Series Finale, "A.D." reveals themselves to be Alex Drake, the twin sister of Spencer . </P> <P> "A" makes appearances as a figure with black leather gloves, a black hood, dark pants, and dark shoes . Throughout the seasons, the story focuses on the mystery of "A". However, "Big A" also sported different disguises, including that of Red Coat, while their ally disguised themselves as The Black Widow, while also donning the Red Coat identity on certain occasions . </P>

Who started the a team in pretty little liars
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