The billionaire founder of fashion giant Mango was out hiking with his son in Spain's Montserrat mountains when he mysteriously plunged more than 150 metres to his death a year and a half ago.

Amid widespread shock at the death of one of Spain's richest men – an entrepreneur who started out in the late 1970s on a Barcelona market stall and ended up head of one of Europe's biggest fashion chains – it wasn't long before questions were being asked.

How could a physically fit 71-year-old suddenly fall from a path suitable for walkers of all abilities?

And why had Isak Andic gone up a mountain with Jonathan, the eldest of his three adult children, with whom he is said to have had a difficult relationship?

Above all, what caused a mysterious pattern of footprints left behind on the remote mountain path?

This week, in a dramatic twist, Jonathan Andic, 45, was arrested on suspicion of pushing his father to his death and formally named as a suspect in what looks set to be an extraordinary patricide trial.

The reasons for this move were revealed in an astonishing 17-page legal document which has been released by the court and seen by the Daily Mail.

Drawn up by the judge overseeing the case, Raquel Nieto Galvan outlined her reasons for deciding to make Jonathan Andic a 'sospechoso' (suspect) and place him under formal investigation.

The judge's decision to publish her pre-trial conclusions is highly unusual given that Jonathan, who protests his innocence, has not yet been charged. Family members, including his siblings and his paternal uncle, believe he is blameless.

In a statement of support this week, his family said 'there does not exist, nor will there exist, legitimate evidence against him'.

The executors of Isak Andic's will have also insisted on Jonathan's innocence, previously saying: 'We have been witness of how the pain of private grief has been aggravated by a public debate that causes greater suffering'.

But not for nothing has the case been dubbed the 'Spanish Succession'. Just like the award-winning TV series starring Brian Cox as an ageing billionaire surrounded by adult children jostling for control of his global empire, the Mango mogul's death has lifted the lid on the real-life tensions at the heart of the wealthy Andic dynasty.

In her report, Judge Galvan touched on the 'bad relationship' between father and the son he once hoped would take his place as his successor at Mango.

In 2014, while taking a year off to sail around the world in his £25million yacht Nirvana Formentera, Isak handed control of the company to Jonathan, who began working for Mango in 2005 and, while still in his 20s, helped his father launch its menswear line.

But while Jonathan was in charge, the company failed to meet its targets, profits plummeted and several senior executives left the company.

Isak quickly took back the reins and installed an outsider as CEO.

According to the writ this caused 'a crisis on a professional, personal and family level, particularly with his father'.

At a lavish company Christmas party two days before his death, some sources say Isak paid particular tribute to the CEO he'd appointed instead of his son, which others speculated may have felt like a slap in the face for Jonathan.

However, a source close to Jonathan insisted there was no ill feeling and, in fact, Jonathan had sent a loving email to his father after the event.

Judge Galvan also referenced Jonathan's 'obsession with money' in her report this week, saying that in WhatsApp messages, believed to have been found on his father's phone, he expressed feelings of 'hatred, resentment and thoughts of death and blaming his father for his situation'.

Jonathan, she said, wanted to find a way to receive his inheritance while his father was still alive 'or for the figure of the father to cease to exist, either in his thoughts or in reality'.

Isak, it is said, was subject to 'emotional manipulation' from Jonathan 'in order to achieve his financial objectives'.

Analysis of messages also revealed that in mid-2024, Jonathan became aware that his father planned to change his will to create a charitable foundation to help the less fortunate.

According to the writ, that precipitated 'a notable change' in Jonathan, who then sought to 'reconcile' with his father.

In her report, Judge Galvan said forensic experts have concluded that footprints on the path from where Isak plunged to his death could not have been caused simply by someone slipping.

His fall, she states, was akin to someone being thrown feet first 'down a toboggan slide'.

Nor, according to autopsy reports, did the business tycoon's body bear the kind of injuries which would normally be seen following an accidental fall. In particular, the judge points out there were no wounds on the palms of his hands, which might have been expected from a person scrambling to save themselves.

The first to break the news of Isak's death, leading Spanish crime journalist Mayka Navarro of the daily newspaper La Vanguardia, told the Daily Mail this week that sources who visited the scene of his demise informed her: 'It's a very strange place for someone to fall'.

'Right from the start there was something odd about the case,' she adds. 'I started hearing from people who said that the relationship between father and son wasn't good and that they had possibly gone up the mountain to smooth things over.'

According to the judge's report, messages later recovered from Isak's phone revealed that he accepted Jonathan's suggestion of a hiking excursion so that they could talk. Spanish media has also reported that he told his usual bodyguards that he wanted to spend time alone with his son.

The two men set out on the morning of Saturday, December 14 in good weather conditions, parking their car and ascending a flight of steps to reach the picturesque Les Feixades trail.

The signposted path, which connects the Salnitre caves in Collbato with the Benedictine Santa Maria de Montserrat Monastery, is in regular use by families and schoolchildren. Much of it is fenced, aside from a 100-metre stretch – somewhere along which Isak met his fate.

What happened at around noon that day now lies at the heart of this ongoing criminal investigation.

While Jonathan called the emergency services at 12.36pm and told the operator his father had slipped, the subsequent accounts he gave of his father's final moments to both the emergency services and police are said to 'contain contradictions', according to Judge Galvan's report.

In one statement to police he said he had been walking four or five metres ahead of his father, who had stopped to take some photographs with his mobile phone. Jonathan said he didn't see his father topple over but, after hearing a stone falling, turned to see him rolling among the bushes.

In another, he said they had been walking together and that he had seen his father 'screaming and falling'. After recovering his body, police found Isak's mobile in the pocket of his trousers and discovered it had been used only at the beginning of the hike and not at the time of his fall, meaning that he couldn't have been taking photos.

Despite these discrepancies the death was initially treated as a tragic mountain accident. The case was provisionally closed in January 2025.

But behind the scenes, the Mossos d'Esquadra regional police force continued their investigations. Among the details which roused their suspicions, according to the legal document seen by the Daily Mail, were the footprints left at the scene.

Forensic experts who conducted four separate simulations concluded that the scuff marks left on the ground by the soles of the dead man's trainers 'had to be performed at least four times in both directions' to achieve a similar print. According to Judge Galvan's report: 'The mountain police state that the action had to be carried out deliberately by applying pressure to the ground and the mark could not have been made accidentally.

'It is concluded that by performing a single forward rubbing motion simulating a slip, it is not possible to generate a footprint like the one located on the day of the events.'

Jonathan's behaviour during the days before that fateful trip also raised suspicions.

While he is said to have told officers that he had only been to the trail a fortnight before his father's death, tracking of his car revealed he visited on three occasions in the week before Isak's death: on December 7, 8 and 10.

In March 2025 the investigation was formally reopened by a court in Martorell near Barcelona.

It was around this time, according to the Spanish judge's legal writ, that Jonathan took a three-day trip to Quito in Ecuador and the phone he owned at the time of his father's death disappeared.

He claimed his mobile had been stolen and all its data lost – something described in the writ as a 'disappearance, under strange circumstances'.

In life, Isak Andic's rags-to-riches story made him a captivating figure in the world of business and fashion. Born in Istanbul, he moved with his Turkish-Jewish family to Catalonia in north-eastern Spain in 1968. His father, who ran a business importing electronics, saved up to send him to the private American School.

He studied business administration in college but dropped out to set up a tiny market stall in Barcelona where he initially sold embroidered cotton blouses imported from Turkey.

It wasn't until he ate a mango during a trip to the Philippines that he decided on a name for his burgeoning brand.

The first Mango clothing store was opened in 1984 on Barcelona's famous Passeig de Gracia.

Today, the company has around 3,000 branches, including more than 100 in the UK and another 15 due to open this year. In 2024, it had a turnover of €3.3billion (£2.8billion).

According to crime journalist Mayka Navarro: 'He was one of those great self-made men who arrived here as an immigrant to sell shirts out of nothing and, with a great deal of astuteness, intelligence and charisma, amassed an incredible fortune. He was clever and attractive and seemed almost to be immortal. The shock when he died was tremendous.'

By the time of his death, Isak was said to have accumulated a personal fortune of €4.5billion (£3.9billion).

In his will he left €5million (£4.3million) to his girlfriend of seven years, the 53-year-old former professional golfer Estefania Knuth.

He divided control of the family holding company Punta Na, which owns 95 per cent of Mango, between Jonathan and his sisters Judith, 42, and Sarah, 27. All three are the product of his marriage to ex-wife Neus Raig Tarrago.

Isak had handed the remaining 5 per cent of the company to his CEO and minority shareholder Toni Ruiz, the man he praised so effusively two days before he died.

Jonathan, who insists his father's death was a freak accident and that their relationship was good, was arrested in Barcelona on Tuesday.

Paraded in handcuffs before Court of Instruction Number 5, his status was upgraded from witness to 'homicide suspect'.

After a closed-door interrogation with his lawyer, he avoided being remanded in custody after surrendering his passport and posting bail of €1million.

He is well-known in Spain, where he is regarded as something of a playboy figure.

His wife is fashion and lifestyle influencer Paula Nata, 37, who in the past has posted glamorous shots of their skiing holidays in St Moritz, as well as stays at the Andic family home on the Balearic island of Formentera. She gave birth to their first child in September last year.

This week his lawyer Cristobal Martell said that 'the homicide theory does not hold up. But, above all, it is painful. It stigmatises an innocent man'.

It is understood that Jonathan, who only answered questions from his defence lawyer in court, now wants to give a statement under oath to the judge once he and his legal team have had time to study the 1,400 pages of case files.

Sources close to the Mango heir said he would be willing to respond to questioning by the investigating judge and a public prosecutor in order to 'refute serious inaccuracies about the death of his father in the police reports'.

It remains to be seen if the evidence against Jonathan Andic is enough to see him brought to trial.

If charged and then later found guilty of homicide he could face up to 15 years in prison. It's also possible he could be charged with the more serious crime of pre-meditated asesinato, which can carry a life sentence.

If there was a time when Isak Andic's life story was seen as nothing less than a fashion fairy tale, then it's clear that the manner of his death – and his son's arrest – has cast a terrible shadow.