The Assassin and The Empire by Sarah J. Maas
A single, decisive mission could mark the start… or the conclusion.
Celaena Sardothien possesses the life of an assassin in its entirety: a refuge to claim as her own, the affection of the charming Sam, and, most importantly, her freedom. However, true liberation can only be attained if she escapes the clutches of her former master, Arobynn Hamel. To achieve lasting freedom, Celaena and Sam embark on a final, audacious mission. Little does she know that acquiring everything also means risking losing it all.
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