Lynn, a top secondary school student living with her father, is accepted into a prestigious school, earning a scholarship for her academic achievements. There, she is befriended by the good-natured but academically challenged Grace. Lynn begins helping Grace cheat in exams after finding out that their teacher has been leaking questions in private tutoring sessions. She is then approached by Grace's rich boyfriend Pat, who offers payment in exchange for also helping him and his friends. Although at first reluctant, Lynn agrees when she finds out that the school took payments of "tea money" from her father, who earns a modest income as a teacher. She devises a system of hand signals, based on certain piano pieces, and uses them to send answers during exams. Her base of clients eventually grows. However, her cheating is inadvertently revealed by Bank, another top student. She is reprimanded by her father and the school, which suspends her scholarship, as well as her chance to apply for an international scholarship at the university level.

Lynn returns to the cheating business when Pat and Grace ask her to help them cheat in the STIC

https://en.wikipedia.org/wiki/Bad_Genius
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