I'm looking for an old (40s - 50s) French medieval adventure movie. I think the main hero is Jean Marais but recently I began to doubt this, because I haven't found anything similar in his filmography.
The final scene had Russian roulette between the hero and the antagonist for the dame, with two glasses of wine (poisoned and still). The antagonist poisoned both glasses, but the hero survived because he had immunity to the poison. He was also a very skilled fencer and raider and had outstanding strength and intelligence.