The Poisoner (2006)

Loudun, October 1947. Leon and Marie Besnard celebrate their 18th wedding anniversary with friends and Ady, a former German prisoner they have "adopted." A few days later, Leon dies. Louise, a friend of the couple's--and probably Leon's mistress--claims that on his deathbed, the deceased told her that Marie was poisoning him. The whole town soon condemns Marie and she is arrested and sent to jail. Did she really kill Léon as well as 12 other family members, as she finds is the charge against her?