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Prison Playbook is a 2017 drama that features Krystal, a member of the South Korean girl group f(x). The drama follows the story of Kim Je-hyuk (Park Hae-soo), a renowned baseball player who is imprisoned after accidentally killing his sister's assailant. Krystal plays the role of Kim Ji-ho, Je-hyuk's younger sister who struggles to cope with her brother's imprisonment and the aftermath of her sister's death.