The trial for the murder of a Luxembourg resident in August 2021 began on Monday morning at the Luxembourg District Court, with his former partner accused of poisoning him during a 2021 trip to Portugal.

Three members of her family are also facing charges for allegedly helping her dispose of his body in a river near Figueira da Foz, roughly halfway between Lisbon and Porto.

As it was initially suspected that the perpetrators could be part of the victim's entourage from Luxembourg, an investigation was also opened here. In March 2022, the victim's partner, her son, her mother, and the mother's partner were all arrested.

The court heard on Monday about the complex family relationships at the heart of the case. All names have been changed to guarantee anonymity.

In August 2021, the victim "Pedro" was on holiday in Portugal with his long-term partner "Ana", accompanied by Ana's adult son "Paulo", her mother "Mariana", and Mariana's partner "Antonio". Police investigations later revealed that Ana and Antonio had been having an affair for some time, even while on that trip together.

Ana reportedly told investigators that Pedro had been abusive, both physically and psychologically. However, other witnesses described Pedro as a quiet, hard-working man, whose relationship with Ana seemed stable as long as he provided her with money, but grew tense whenever he refused to pay. Ana was receiving Luxembourg's guaranteed minimum income (RMG) at the time.

The group's attempt to cover their tracks quickly fell apart. About a week after the killing, a post appeared on Pedro's Facebook page announcing a breakup with "the love of his life". But by then, Pedro's sister had already reported him missing, and Portuguese police had recovered his body. Meanwhile, Ana was seen withdrawing cash from Pedro's bank account using his cards. Footage from CCTV clearly shows her at the ATM, and she had also inquired about his life insurance.

By that time, the family's phones were already under surveillance. Investigators recorded a conversation in which Mariana instructed her grandson Paulo on what to tell the police.

Forensic analysis of electronic devices later revealed that Antonio had searched online a month before the crime for "a poison that leaves no trace" and even attempted to order a "poison to kill people" from a Brazilian e-commerce site. The judge commented that if the story had not ended so tragically, "it could almost be mistaken for a telenovela".

According to the investigation, Ana acted with remarkable composure. She sent her cousin to a pharmacy to purchase the insecticide, claiming it was for Pedro's sister, and Mariana went along. After buying the poison, the two women reportedly stopped to order a roasted piglet for a party that took place three days after the murder.

While her relatives were at the pharmacy, Ana appeared to be scouting a location to dispose of the body. In a message to Mariana, she wrote that she had already found a cemetery. Investigators told the court that photos from the party, held shortly afterwards, show Ana dancing and smiling.

Although there is little direct physical evidence, the police uncovered additional clues in text messages. In one exchange, Mariana joked that her daughter should now "find herself a new rich man", to which Ana replied, "Are you crazy? You want me to throw him into the Moselle after five years?" The two women reportedly laughed about it.

The trial is set to continue on Tuesday.