Mona Vanderwaal

Hanna Marin's best friend, Mona initially harbors a grudge against the protagonists, using her intelligence and resources to torment them anonymously as "A". In the third season of the TV series, Mona gains a partner who eventually takes control from her. Afterward, she forms an unstable alliance with the protagonists, becoming a victim of her own creation. Considered the most knowledgeable character in the series,[1] Mona is versed in computer hacking, foreign languages, singing, empathy, and manipulation. Though introduced as a villainess, she eventually takes steps toward redemption. Mona is the first 'A' in the show and the book.Mona is introduced as an alluring and witty teenager, whose full intelligence is gradually revealed as the series progresses.[10]?It is eventually discovered that she can speak French, hack computers, sing, and do voice impressions.[6][10][11]?Her high IQ is further established in the Season 3 episode "Mona-Mania", when she competes against rival Spencer