This story began a morning of June; Arno wandered alone in the streets of Rouen, only the sound of his clapping footsteps on the pavement disturbed the silence of the sleeping city. Since he had left his small studio, the only humans he had met were a few tramps lying on benches surrounded by dead bottles.

Arno Calane was a police inspector and once again he was heading to a crime scene... It was the fourth time in two months and he was only hoping for one thing: this time they would find a clue.

His partner, Richard Rigaud was a veteran, to tell the truth, this investigation would certainly be the last of his long career. Yet, even he had never seen anything like that, the murders were committed in the middle of town in daylight and yet no clue, no witness, nothing...

It was almost six when he arrived on the scene; Richard was waiting for him, already bent over one of the corpses searching of a possible clue. As he approached, Arno's brain gradually started to run and the similarities with the 3 previous cases appeared to him. Two bodies lying on the ground in the middle of the street without care being taken to hide them. One was bathed in his blood while the other had no apparent wound; in fact this second victim seemed to sleep peacefully. This time there were 2 women but in all 4 cases the unscathed victim was a woman. Besides, there was no sign of a struggle here.

- So, what do you think?

Richard had joined him and, as usual, asked him to give his opinion on the crime scene. For a year they had been working together, it was like a ritual, Arno gave him his opinion and Richard completed with his own analysis. This was his vision of field training and it suited Arno perfectly because it made him much more active than most newbies who often spend months watching their mentor play cowboy before finally having the right to make the smallest hypothesis.

Arno explained the points he had observed while examining Richard's reactions. Richard was listening to him without looking at him, his eyes were set on one of the corpses, something had obviously caught his attention. Unconsciously, Arno also began to observe the corpse but no element really caught his attention.

Once done, Richard turned to Arno with a broad smile:

- Looks like you're starting to get a good eye. A little more training and you'll be as good as me... Now what do you deduce?

Arno thinks again:

- It seems hard to imagine our killer murdering two people in the street without leaving any trace and without neither of them having had the time to scream or defend themselves... For me, the murders took place somewhere else; this crime scene is only a staging.

It's very likely indeed...

Richard paused a moment before resuming:

Look, she has a tattoo on her shoulder... I feel like I saw a similar one on the previous victim...

Arno remembered noting such detail; he quickly flipped through his notebook to find his notes related to the previous murders..:

- It's right there! Tattoo half erased on the shoulder... We may have our connection between the victims...