François Civil, Vincent Cassel, Pio Marmaï and Romain Duris star in this historical action adventure based on the novel by Alexandre Dumas. D'Artagnan (Civil) travels to Paris with the ambition of becoming one of King Louis XIII (Louis Garrel)'s Musketeers of the Guard. A blunder forces D'Artagnan into the path of the Three Musketeers: Athos (Cassel), Porthos (Marmaï) and Aramis (Duris), who challenge him to a duel. Impressed by D'Artagnan's talents, the Musketeers befriend him, and he is soon swept up in the adventures of the trio, putting his fighting skills to use when he is tasked with protecting Queen Anne (Vicky Krieps) from a scheme which threatens to see her accused of treason and meet her untimely demise.