Sam (Karen Gillian) was only 12 years old when her mother, Scarlet (Lena Headey), an elite assassin, was forced to abandon her. Sam was raised by the Company, a crime syndicate her mother worked for. Now, fifteen years later, Sam, who has followed in her mother’s footsteps, is a formidable assassin. He uses his “talent” to erase the traces of the union’s most dangerous failures. As efficient as she is, Sam is just as loyal.
But when a high-risk hit fails, Sam has to choose between loyalty to the Firm and protecting an innocent 8-year-old girl, Emily (Chloe Coleman). Now a target herself, Sam has only one chance if he wants to escape with his life: to team up with her mother and her associates (Angela Basset, Michelle Yeoh and Carla Gugino), known as the “Librarians”.
These three generations of women must now learn to trust each other, face the Company and their army of acolytes, and unleash hell against those who could kidnap what is most precious in this world.