A French murder trial that opened Monday has transfixed the public because of the mystery at its core: where is the victim's body?

Cédric Jubillar, a 38-year-old painter-decorator, is accused of killing his wife Delphine nearly five years ago in a fit of jealous rage. He has always denied the charges, and, other than circumstantial evidence, investigators have struggled to build a case. There is no body, no blood, no confession, and no witness.

With its unexplained central fact and its cast of characters from small-town southern France, the affair has become a social media sensation.

Self-declared investigators have set up countless chat groups where they swap theories and share testimony – much to the irritation of police and families. These groups are the equivalent of the bistro counter – but with more people, said psychoanalyst Patrick Avrane, author of a book on attitudes to crime. Everyone constructs the theory that suits him or her the best.

The Jubillar mystery began at the height of the Covid lockdown when – in the early hours of 16 December 2020 – Cédric Jubillar contacted the gendarmes to report that his wife had gone missing. Delphine, who was 33 at the time, was a night nurse in a clinic not far from their home in Cagnac-les-Mines, in the south-western Occitania region. The couple had two children, aged six and 18 months.

Police discovered that the Jubillars did not have a happy relationship. Cédric was a habitual cannabis user and barely held a job, while Delphine was romantically involved with another man and discussions of divorce were happening.

Extensive searches in the surrounding countryside did not yield Delphine's body, but a case gradually built against her husband, who was detained mid-2021. The prosecution will argue that Cédric had a motive due to their impending split, pointing to suspicious actions on the night of Delphine's disappearance and signs of a struggle.

Cédric's character will also be scrutinized, with witnesses expected to testify about his threatening behavior towards Delphine and his apparent indifference following her disappearance. Some acquaintances have claimed he confessed to her murder, yet the defense will challenge these testimonies and emphasize the lack of physical evidence.

Discussing the trial's public intrigue, writer Thibault de Montaigu likened it to the works of detective novelist Georges Simenon. He highlighted the paradox of a person perceived as a likely perpetrator lacking the evidence to substantiate such beliefs.

This trial is anticipated to last four weeks, with over 65 witnesses and 11 experts, convening amidst a public eager to solve the puzzle of Delphine Jubillar's fate.