Yara Gambirasio was a 13-year-old gymnastics enthusiast who went missing in Italy in November of 2010. It was snowing heavily that evening. At around 6 pm she left a gym, 700 meters from her home, in a small, post-war satellite town, near the city of Bergamo, called Brembate di Sopra, a town close to Milan.

It is that kind of place where nothing happens. It is hardly open even by day – not even its church. By 9 pm, not a single bar is open. She never made it home. Her parents repeatedly tried to contact her on her mobile phone. There was no reply. At 7.30 pm, they called the police.

Three months after Gambirasio’s disappearance – on 25th February 2011 – her partly decomposed and frozen corpse was found in a field 10 km from her home. Someone in Italy had done this, and the authorities were going to find that someone even if they had to test every goddamn person in the country. That my friend is not hyperbole.

Yara had a dozen knife lacerations to her throat and back, which were too superficial to have caused her death. She had lost consciousness and died of exposure; investigators concluded. Despite the time that had passed since her death, forensic scientists found several good samples of DNA material on her.

But when no matches were found in the existing database, authorities simply expanded that database — they took close to 22000 voluntary DNA swabs from people living in the area. Eventually, they got a partial hit: Damiano Guerinoni was not an exact match, but testing indicated that someone in his family might be.

Unfortunately, that family was larger than some entire towns: his father had 11 brothers and sisters. The investigators kept looking until they finally got a closer match from Damiano’s uncle, bus driver Giuseppe Guerinoni.

Case closed, right? Not really, since Guiseppe had died 11 years earlier. But the police who were not ready to give up went to the home of his widow in a small town in northern Italy. The widow produced a box of documents that contained her husband’s paper driving licence, to which was affixed a Marca da bollo (a postage stamp used for tax purposes). Perhaps – they reasoned – the back of the stamp would contain the dead man’s DNA, if, that is, he had licked the stamp himself before sticking it on to the licence.

Now, what is the probability of that! So they were astounded when, a couple of weeks later, results came back from the lab showing that the DNA on the stamp was a close match to DNA found on the underpants and leggings of the murdered girl. Since Guiseppe was dead long back, his children were tested and even they were cleared. And he had no other offspring that his wife knew of.

Note that we said, “knew of.”

Apparently, our driver friend had a rather “active” social life outside the bounds of his marriage and had a secret son somewhere along the way. Authorities were now looking for a bastard, both figuratively and literally.

After putting together an exhaustive list of 532 women who Casanova Geurinoni had or could have slept with, they tested all of them, twice, and found a match with 67-year-old woman Ester Arzuffi. It turned out that her oldest two children, twins, had been fathered by ol’ Giuseppe. The female twin was quickly ruled out, which left Ester’s son: 43-year-old Massimo Giuseppe Bossetti.

Police quickly got a DNA sample from Massimo under the guise of a Breathalyzer test — it was a match to the DNA found at the crime scene. He was sentenced to life in prison, deservingly.

The Tale of the most gripping investigation that Italy has ever seen will always be remembered. Yara, RIP