Death Walks on High Heels

Nicole Rochard learns that her father, Ernest Rochard, was stabbed to death on a train. The police question her about missing diamonds tied to his past heists. The revelation casts a pall over the investigation and Nicole's security.

It is explained that Ernest Rochard was a famed thief who had since tried to go straight, but the diamonds' fate remains uncertain. The backstory hints that old criminal ties still threaten Nicole. The police weigh whether the diamond theft is connected to her father's past.

Nicole starts receiving threatening calls from a mysterious caller using a voice changer. The calls heighten her fear and signal that someone is watching her. She grows increasingly paranoid about who might be behind the menace.

The man with the voice changer appears in Nicole's life physically, wearing a black ski-mask and threatening her with a razor. He demands to know where the diamonds are. The threat intensifies Nicole's sense of danger.

Nicole goes to her boyfriend Michel's apartment and spends the night there. The events leave her unsettled and more distrustful of those around her. The ambiguous situation foreshadows a wider web of deceit.

In the morning, Nicole discovers Michel has blue contact lenses and flees, convinced he is the masked man. She meets Dr. Robert Matthews, a British eye-surgeon, who agrees to take her away from Paris. They plan to fly to London together.

Nicole and Matthews fly to London, where she goes on a shopping spree and he takes her to his countryside retreat. Locals are wary, and Matthews tries to present Nicole as his wife while his money is said to come from his wife, Vanessa. The sense of deception deepens.

The village is watched by Hallory, a sinister handyman with a false hand, and Captain Lenny, among others who spy on Matthews' house. A telescope observer and a mysterious woman in black offer large sums to Nicole, heightening the sense of manipulation in the village.

Matthews returns to London to perform an eye operation on an elderly man named Smith; after the procedure, a mysterious woman shoots him in the shoulder, sending the investigation into high gear. The doctor surviving the shot deepens the mystery around who targeted him.

Inspector Baxter leads the police inquiry, focusing on fine details such as the drugged Matthews asking for Nicole post-surgery. Vanessa and Smith deny knowing Nicole, while others are questioned to piece together the timeline.

Nicole's body is fished out of the water by a local fisherman, and Michel is questioned by the police. Captain Lenny is identified as a spy who had been watching the village nightly, adding a new layer to the motive behind the events.

Vanessa had paid Nicole to leave Matthews, and blue contact lenses on Michel are revealed to be a Matthews frame-up. It is disclosed that Matthews and Rochard were partners in the diamond scheme, with Rochard being double-crossed for the diamonds. The diamonds are finally recovered, and the investigation closes with Baxter and Bergson seeing Michel off at the airport.