The first part introduces Sylvain, Marquis of Bois-Doré, a companion-in-arms of late king Henry IV of France.
The marquis feels deep love for Lauriane de Beuvre, a daughter of his friend and neighbour, 30 years younger than him.
The latter falls in love with Lauriane whose heart is torn by sincere respect for noble, generous but elderly Sylvain and affection to young Mario.
The serial is distinguished by an entertaining plot, superb acting of G.Marchal (Sylvain) and Y. Folliot (Lauriane), picturesque scenery, and accurate representation of historical background.
“This is an eventful yarn, involving many subplots, it is par excellence the perfect swashbuckler, which after being popular in the first part of the sixties in the French theaters became mini-series in the seventies..”