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, Sybille is one of two women practising the occult. Despite her name, she is not the parallel of Sybil Stamfordis--that would be another woman named Irène instead. Sybille's role makes her closer as a parallel, to Thyrza Grey.
Unique to this adaptation, there are only two women, not three. Furthermore, they are actually known to Eugène Dacosta the Mr Venables parallel as the women operate from a tent in a fair ground and Dacosta actually owns the fair.
Irène has the role of the medium. Sybille's role is more that of the necromancer. She does the summoning and communicating with the spirits which "take over" the body of Irène. Sybille is the leader of the team and she can be seen goading Irène to do her part and threatening her when she wants to quit. Like in the original, she is probably the only one who understands the bigger picture of the part she plays in the "murder-for-a-price" operation. She is seen receiving notes and payments from the person directing the operation, for example. However it is not clear if she knows she is just a misdirection or if she actually believes that her occult actually causes the deaths of the victims.
Sybille is portrayed by Valérie Dashwood.