The movie was set in some medieval period (swords/armor). I remember only one scene. So there is some kind of a monster in the building (a castle, I guess). Warriors gathered all women and children into a room and told them to lock it from the inside. Then the men realise the monster got into it somehow, screams and all, but when they finally opened the door, I think all of those inside were dead.
I’d say the movie has to be at least 10 years old, in color.
Le pacte des loups?
Nope, though the description looked promising.