Academy Award-nominated screenwriter Randall Wallace (Braveheart) makes his directorial debut with this rousing old-fashioned drama inspired by Alexandre Dumas's tales of the three Musketeers. France in 1660 is on the verge of catastrophe brought on by the irresponsible and cruel policies of King Louis XIV (Leonardo DiCaprio). In middle age, the legendary Musketeers can only pine over their former glory days — Aramis (Jeremy Irons) has become a priest; Athos (John Malkovich) lavishes his attention on his son Raoul (Peter Sarsgaard); and Porthos (Gerard Depardieu) laments his waning sexual prowess.

When the king sends Raoul off to die in battle so he can seduce his fiancee (Judith Godreche), the tragedy sets in motion a reunion of the three Musketeers to save France and to put on the throne a leader worthy of respect and devotion. Their scheme involves a young man in prison, his identity hidden behind an iron mask. The Musketeers' plan compels their close friend D'Artagnan (Gabriel Byrne), Captain of the Musketeers, to search his soul concerning his loyalty to the king and his service to Queen Anne (Ann Parillaud).

Although there are plenty of lively action sequences in the film, the thematic core involves the efforts of the three Musketeers to seek justice and to nurture hopeful hearts. The odds certainly seem against them, but they are willing to risk everything. The motto they lived by in their glorious youth, "One for all, all for one," still applies. The Man in the Iron Mask reveals how important it is in middle age to keep one's spiritual ideals alive and shining.