A cousin of Monaco’s reigning prince walked out of a nightclub leaning on someone, and investigators still cannot say how he came to fall to his death hours later.
Toxicology results from the autopsy on Antoine de Massy, 29, had not been released as of Oct. 31, 2026, and the circumstances of the fall that killed him remain unclear. De Massy, a first cousin once removed of Prince Albert II, was found dead on Sunday, Oct. 25, in a small park behind Villa Sauber, the home of the New National Museum of Monaco.
Pathologists carried out the autopsy on Tuesday, Oct. 27. Autopsy findings indicate he fell about 13 meters, or roughly 43 feet, from the Boulevard du Larvotto, which runs along the park.
His family reported him missing after he failed to show up for a family lunch. Witnesses had seen him stumbling out of a nightclub in the early hours of that Sunday morning, leaning on someone. His body turned up in the park that evening.
Late on Monday, Oct. 26, Monaco authorities said a man was in custody. They had also opened an investigation into the death of a member of the princely family. The cause of death was still being determined at that point. Officers arrested the man, a Ukrainian national, that same Monday after CCTV footage placed him near the spot where the body was found.
The suspect is 42 and has made his home in Monaco for the past three decades. Investigators established that he had been in contact with de Massy.
Prosecutors charged him with involuntary manslaughter and with failing to help someone in danger, and said it is still unclear what part, if any, he played in the death. “All hypotheses are on the table, including that of a simple accident,” the prosecutors’ office said in a statement.
A judge saw the man on Wednesday, Oct. 28, and he declined to answer questions, having disputed the allegations during police questioning. Pretrial detention followed.
Stéphane Thibault, Monaco’s prosecutor general, said the alleged offenses may not all date from the same moment.
Christian de Massy, Antoine’s father, rejected the accident theory and told Italian media that he rules out both an accident and suicide. He said his son did not know the 42-year-old man.
De Massy was active in Monaco’s blockchain scene, co-founded the “Association Cryptographique de Monte-Carlo.” He has been rumored to have ties to the exchange Zondacrypto, which collapsed in 2026 and is under investigation by Polish authorities on suspicion of fraud and money laundering. The connection remains unproven, and reports linking de Massy to a cryptocurrency scandal are unverified.
Tennis Balls Among the Flowers
Mourners built a makeshift memorial near the spot where he died, leaving flowers, candles, a Monaco flag and tennis balls in tribute to his love of the sport.
The Prince’s Palace said on Monday, Oct. 26, that Albert II and his wife, Princess Charlène, were saddened by the death. The palace remembered him as an avid player from a family long tied to tennis in Monaco.
De Massy was a grandson of Princess Antoinette, the elder sister of Albert’s father, Prince Rainier III. His grandmother died in 2011 at age 90. His mother is Cécile Gelabale, and his paternal grandfather, Alexandre-Athenase Noghes, was an international tennis player.
From Bollettieri’s Academy to Instant Tech
Tennis came before the tech world. In a 2012 interview, de Massy said his father first put a racket in his hands when he was three, and he described a dream of reaching the world’s top ranking. He hoped to represent Monaco at the Olympics. His family relocated to Florida while he was young so he could train at the Nick Bollettieri Tennis Academy.
He later turned to business, co-founding the technology firm Instant Tech, a platform that connects local businesses with customers and handles instant reservations and payments.
One of his last public appearances came at the traditional Te Deum Mass for Monaco’s National Day in November 2025. He otherwise preferred to stay out of Monte Carlo’s social scene.
A funeral Mass is scheduled for Wednesday, Nov. 4, at Monaco Cathedral, with burial in Monaco to follow.
An Arson Death and a New Name
In a separate case, Ted Maher was convicted of arson in the 1999 fire that killed billionaire banker Edmond Safra and nurse Vivian Torrente in Monte Carlo. Released in 2007, he later reinvented himself in the U.S. as Jon Green, married physician Kim Lark in 2020, and in 2025 was convicted in New Mexico of soliciting her murder after the couple became estranged.
