In Le cheval pâle, the French Télévisions film adaptation of Agatha Christie's The Pale Horse, for the Les Petits Meurtres d'Agatha Christie TV series, Lucille Marchal is the step-mother of Francine Marchal who is the parallel of Thomasina Tuckerton in the original story.
Like the Mrs Tuckerton in the original story, Lucille did not get on well with her step-daughter Francine. Francine had inherited most of her late father's estate and would gain control over it in a few months when she came of age. This worried Lucille because she would then stand to lose everything. Lucille's role in bringing about her step-daughter's death is made more explicit in the adaptation. Alice Avril and Marlène Leroy actually saw her exiting the tent of the occult women at the fair.
Soon after Francine's death, commissaire Laurence wanted an autopsy on Francine but Tricard forbade it because Lucille knew a lot of influential people and Laurence had no good grounds for wanting one. In any case, Lucille acted quickly to have the body cremated to forestall any attempt at an autopsy. She also put up the large house they lived in for sale.
Laurence went in undercover pretending to be interested in buying the house. After viewing, he said he did not have enough ready money but was expecting some from an elderly aunt who was invalid but somehow kept clinging on to life. Taking the bait, Lucille told him of a murder-for-payment service and gave him the contact of one Bonnet and the pass phrase he must use when meeting him.
At the end of the episode, Laurence says that he had interrogated Lucille and she had broken down and had yielded a full confession.
Lucille Marchal is portrayed by Anne-Sophie Girard.