The list sent by Ms. Zapata contained about ten names, including a certain David Leterrier met by Agathe three times. The inspectors deduced that it was the David whom Jade Henault had told them about and who had been expelled from the Jewel after his too insistent advances.

The director had revealed to them that he had put up with his eviction and had begun to harass the young woman, calling her up to twenty times the same day, leaving her obscene voice and written messages.

They went to his work, an international investment fund situated at La Défense. Leterrier was Partner in the capital division. The office was located in one of the glass towers of the business district, facing the vast esplanade of La Défense and its large arch with post-modern architecture.

The inspectors waited at the reception before being taken to the Partner's office, which had a breathtaking view of the arch. The decoration was very masculine with its woods in dark tones and its deep slate grey carpet.

Leterrier was sitting at his desk, facing the window. He turned by a slow theatrical rotation of his chair. Alex stopped rolling his eyes. The man was of an important size, with prominent biceps and broad square shoulders accentuated by the cut of his great designer jacket. He did not correspond to the image that one could make of the typical financier.

He greeted them badly and invited them to sit down.

"To what do I owe this visit, inspectors? I swear I have not broken any financial market rules, in the last few days at least.

Alex had little of the joke.

- We are not of the National Financial Prosecutor's Office but of the Judicial Police, she replied without blinking. We're investigating a crime committed three weeks ago, which you may have read about in the papers.

- No, enlighten me.

- A girl named Agathe de la Badie was found dead in the Seine.

- That name doesn't ring a bell.

- She was known to some under her alias. Rubis. Does that mean anything to you?

He lightened his throat and crossed his hands on his leather underside.

- It depends. Will I need my lawyer?

- We interview everyone who knew her from near and far, especially her clients. So this is a routine interrogation for the moment, Mr. Leterrier, replied Fred in his posed voice.

The man bulged in his seat.

- In this case, yes, I did. But you already know that. Just as you must know about my, say, little incartade.

- And what incartade are you talking about?

- You know. The calls. The messages a little grivy.

- In legal language, it is called "sexual harassment" and not "incartade", the inspector said.

He swept the air with his hand.

- You can call it whatever you want. It wasn't important.

- That's up to us. Where were you on the weekend of September 3-4?

- Let me check my calendar.

He opened a black notebook and quickly turned the pages until he reached the requested date.

- Ah, yes, it was my wife's birthday weekend. We went to our second home in Le Touquet.

- Have you been there all weekend?

- Of course.

- And you or your wife never went away?

- Not for a moment. Believe me, I didn't miss it. The older this woman gets, the more unbearable she becomes.

Inspector Jolivet held a sigh of exasperation.

- We'll need the number of your wife and two guests, if any, to confirm your alibi, he says.

- I will ask you to see this with my assistant before leaving.

- We're still here, Mr. Leterrier. How long were you a client of the Jewel before you were kicked out?

The inspector saw the man's jaw contract. Hit.

- A little over four years, I think, he said, trying to control himself.

- So you were what you might call a regular.

- I was a very good client. Ms. Zapata didn't handle what happened very well. I made sure to tell the many friends I had recommended the Jewel to and who became customers thanks to me.

- It must have been hard to digest. Picking on Rubis was a way to get revenge, wasn't it, Mr. Leterrier? You wanted her to pay for the humiliation she put you through.

He refrained from responding to the provocation.

- But was that the only way you found ? You couldn't stand to be rejected by a girl, not to mention a little whore. You had to go further.

- You're wrong, he ranted. Check my alibi.

- You knew she was pregnant, she told you and threatened to tell your wife. You had to shut her up.

He jumped out of his chair.

- That is enough, he said in a loud voice. If you have any proof of what you are saying, stop me. Otherwise, I will ask you to leave my office immediately."

The inspectors stopped in the assistant's office and took the requested contacts. Once outside, protected from prying ears, Fred turned to his colleague and asked in a disapproving tone:

" Was it really necessary?

- You have to pull them out of their way from time to time. I found that interesting, didn't you?

- All you've been able to establish is that this guy has a problem with self-control. It doesn't prove he's capable of killing.

- On the contrary, it proves that he has an angry and impulsive temperament, which fits well with the lack of premeditation of the murder. The culprit is a person of sufficient strength to tighten a sail rope until the victim's strangulation and move a body from one place to another to ultimately throw it into the Seine. Have you seen his biceps?

- He maybe just forced on his breakfast coffee fix, sighed the inspector into the cockpit of their car. His alibi looks solid.

- And that's too bad, Alex says as he was starting the car. He would have made an ideal suspect."

***

Their next destination was the Faculty of Law located at 92, Assas road in the 6th district of the capital. The University Paris II was one of the most famous in the country and disputed with the Sorbonne the title of best law university in France.

They showed their plaque to the security guards at the entrance and entered the vast hall with its walls clad with flat-screen screens that broadcast messages to students and the floor reflecting long red and white neon lights that illuminated the ceiling.

They went to the Undergraduate College Office where an assistant pointed them to Tutorial Room 403. They snuck in among the students who crowded into the maze of corridors and got lost several times before finding the staircase leading to the hall.

"It's a fucking labyrinth here, mauled the inspector as she went up the steps two by two.

- Still happy it's not on the top floor, says his colleague, out of breath.

- We'll have to get back to sports, Freddy!

- Not everyone is a step addict like you.

- Ah ah, very funny."

The course had just ended when they arrived. Hungry students packed their belongings in a hubbub of chair scrapes and passionate discussions.

"How much did you get?

- C+, what about you?

- C-, I don't understand the rating.

- That's already ten points higher than the class average, reassured his classmate. Come on, don't worry, it's only the first grade of the year."

Alex looked up. The other conversations revolved around the same subject. The law students seemed very competitive to her. She knew the reputation of the college that was no longer to present.

Fred approached the teacher, a tall, old man with short cut pepper and salt hair and an aquiline nose. He stood in front of his worn leather bag, answering questions from a young student. Three others were waiting behind.

"Mr. Millet?

- Just a moment, he says, without turning away from the student's copy.

- It's the police, sir.

All eyes converged on the inspector and discussions ceased.

- Can we talk to you privately?

- Um... yes, of course. You heard, young people, the professor called out to the students who were lingering. Please evacuate! I will answer the remaining questions by email or during the course next week.

When the room was empty, he closed the door and leaned on his table. He seemed worried.

- Is this about Thea?

The inspectors exchanged a look.

- Thea, Fred repeated.

- Yes, Agathe. Agathe de la Badie.

- Is that what you called her, Thea?"

The man blushed and crossed his arms on his chest.

"Yes, I... Sorry, I shouldn't have.

- You had to be really close to Agathe to use that nickname, the inspector noted.

- I was her teacher for two years, which is rather rare here. Thea, pardon me, Agathe was a brilliant student. I had some very interesting discussions with her.

- What were these discussions about?

- Oh you know, reversals of case law, positions of legal doctrine, that sort of things.

- Were you just discussing law with your student, professor?

- Sorry?"

He seemed more and more nervous.

Alex wondered when he would eventually crack. It was only a matter of time.

She pulled a chair to a table at the back and stretched her long legs. She had never been the type of student to put herself in the front row and lift a hectic finger at each of the teacher's questions.

She felt better in the back. From there, she could see everything that was going on in the classroom. Her gaze lingered on the professor. She had to admit that he had a certain charm, in a tortured intellectual style, but he was more to the liking of Fred than of her own.

"You like that, I guess, she says, raising her voice to be heard from the back of the room. To be listened to, admired by all those young people who drink your words while you unpack your knowledge.

- I'm too old to be moved by all this, he said, annoyed.

- But not with Thea. With her, it was special. What made you fall for it? And don't give us the brilliant brain trick, everyone in this room knows it's bullshit.

- I don't know what you...

- We found the e-mails you were exchanging, Professor. What you were telling her had nothing to do with the only subject you were supposed to teach. Is that right?"

He seemed troubled by this diversion.

"Ah, yes, did he flout. More specific contract law...

- I don't care, actually. That's not what you were interested in.

He scratched his ear.

- Please don't shout it so loud, someone might hear you.

- I can yell louder if I want. Unless you decide to talk.

- Okay, okay.

His foot was caught in a nervous twitch.

- When did you start seeing her? Detective Jolivet asked gently.

- At the beginning of the second semester in the first year. She insisted we go for coffee. She said she found me interesting. It's been so long since something like that happened to me... it's been stronger than my will.

- How long did it last?

- A few months. We saw each other during the summer break. I ended the break, it was too dangerous for my career.

The inspector got a few inches closer to him.

- No. That's not why you stopped it.

The teacher's lips sprang.

- What do you mean?

- She was pregnant with you. She wanted you to raise the child together, right? You weren't for it. You wanted her to have an abortion. It was just a fling after all, a little adventure like there are hundreds between teachers and students every year. You did not understand that she wanted more. She, however brilliant, must have been well aware of the terms of your tacit contract.

- Oh my God, I'm a monster!"

He collapsed on his chair, his head in his hands.

"You used her for your own good. You abused her youth, her credulity while Thea fell in love with you.

- Lord, forgive me, he implored with his hands in prayer.

- But it wasn't enough. You also had to kill her to keep her from talking.

- No. Everything but not that!

He had a look of torture.

- You said yourself, you were risking your career.

- I could never have!

- Where were you on the night of September 4-5, Mr. Millet, asked the inspector, breaking down every word.

- Home! I was home preparing for my Monday morning session, as I do every Sunday evening.

- Can anyone confirm this?

- I live alone with my dog. Neighbours may have heard the music, I need it to focus.

- In other words, you have no alibi for the night of the murder, Professor."

Alex got up and walked quietly through the rows of tables, kicking the chairs that were standing over. The teacher shuddered at each of the scrapes of iron against the hard ground.

"Do you like sailing, Mr. Millet? She finally asks. I noticed the holds on your palms.

- I have a small boat moored in the south, yes. I sail from time to time when I can. I even took Thea there this summer. She loved it. She was so lively, so awake. She was interested in everything.

The inspectors exchanged a look.

- What type of rope do you use for sailing?

- Hemp rope is not unusual. Why?

Alex stopped at his height.

- You'll have to follow us to the station, Professor," she says, handcuffing him.