The Man in the Iron Mask by Alexandre Dumas

The Man in the Iron Mask is the final episode in the cycle of novels featuring Dumas celebrated foursome of D Artagnan, Athos, Porthos and Aramis, who first appeared in The Three Musketeers. Some thirty-five years on, the bonds of comradeship are under strain as they end up on different sides in a power struggle that may undermine the young Louis XIV and change the face of the French monarchy...