While running the vacuum cleaner at the police station one night, Morgane glimpses an ongoing-investigation file, spots an error, and can't resist the urge to correct it.

Morgane is assigned to a new investigation after a man is found dead in the bathtub of his hotel room. She concludes he was murdered after a drink in the hotel bar.

The body of a veterinarian is discovered at her clinic. Everything seems to indicate death from natural causes, but Morgane suspects the young woman was poisoned.

When the wealthy owner of a chain of luxury hotels reports the disappearance of his two granddaughters, Morgane investigates.

Paramedics manage to revive a translator who was found near death with a plastic bag over his head. But Morgane wonders whether someone was truly trying to kill him.

A man is found beaten to death with a cryptic message stuffed in his mouth: "For Josepha." Morgane investigates with her daughter Théa, who is shadowing her for the week.