This story is set in the 13th century, in Britain, where Lancelot, who was raised by Vivian, the Lady of the Lake, becomes one the Knight of the Round Tables and falls secretly in love with Guinevere, the wife of King Arthur, for whom he wants to accomplish many deeds.

Marie-Christine Barrault
as Reine Guinevere

Tony Taffin
as Roi Arthur

Robert Favart
as le Roi Pêcheur

Jacques Weber
as Gauvain

Arlette Téphany
as Reine Hélène

Jean Chevrier
as Roi Ban

Jean Bouvier
as le chapelain

Anne Saint-Mor
as Viviane, Dame du Lac

Jean-Pierre Bernard
as Sénéchal Keu

Marianik Revillon
as Saraïde