This is an adaptation of E. Lockhart’s best-selling young adult novel of the same name. 　　The series focuses on the theme of the results of one’s mistakes and revolves around the affluent and seemingly perfect Sinclairs, who enjoy spending every summer gathering on their secret island. However, something strange happens to one of the members of the family, Cadence, in the summer of her 15th year. Two years later, she and the three other “Liars” Johnny, Mirren, and Gat re-emerge to stir Cadence to recall the incident. “A tragic love story and an amnesia thriller set on a privately owned island off the coast of Massachusetts,” the logline further elaborates.