The family of Greek heiress Marissa Lemos have demanded accountability a year after she died hours after being discharged from University College London Hospital (UCLH) following treatment for an insect bite.
Ms Lemos, 30, was found dead in bed by a housekeeper at her family’s townhouse in Knightsbridge, central London, on September 11 last year.
Her parents, Bessy and shipping tycoon Diamantis Lemos, say she was visibly unwell when she was sent home from hospital. They are now preparing legal action over alleged clinical negligence while still waiting for an official cause of death.
Ms Lemos had developed itching, dizziness, a high temperature and signs of infection after being bitten by an insect. She initially sought help at the Leaders in Oncology Care centre in Harley Street, where she had previously received chemotherapy.
After blood tests, an antibiotics drip and antihistamine treatment, staff arranged for her to be taken by ambulance to UCLH on September 10, 2025, because of the seriousness of her condition.
Her family say she was assessed by trainee medics rather than a doctor and was discharged at about 6.30pm with antibiotics. They claim the initial diagnosis referred to the toxic effect of venom caused by an animal or insect bite.
In one of her final messages to a friend, Ms Lemos wrote: “Nobody is checking up on me, nobody is coming.” She returned home at about 8pm, took her medication and went to bed, but never woke up.
Family still waiting for answers over Marissa Lemos death
Ms Lemos’s mother said the family had been seeking answers since her daughter died, but had yet to receive a copy of the post-mortem results.
“We are very frustrated. It is heartbreaking,” Mrs Lemos said. “We cannot believe we are in the UK in 2026 and no one can tell us how our daughter died when she was hospitalised a few hours before her death.”
A post-mortem was carried out nearly two weeks after Ms Lemos’s death, delaying her funeral and burial in Athens. After waiting almost a year for the results, the family were told that the cause of death could not be determined.
They are also awaiting toxicology testing which, they say, was completed on June 25. The Metropolitan Police have told the family that microbiology tests still need to be carried out and interpreted by a specialist before the coroner decides whether an inquest is required.
“We will never have peace unless we find out the cause of her death and who is to blame for this catastrophic outcome,” Mrs Lemos said. “We’ve been left in the dark and the system needs to be changed.”
The family held a memorial service in Athens last Friday to mark the first anniversary of Ms Lemos’s death.
“They should have kept her that night,” Mrs Lemos said. “After all these tests, we are here today after a year and we still don’t know the cause of her death.”
Ms Lemos was born and raised in London and lived with her parents and twin brothers. She had recently returned from a holiday on the Greek island of Porto Cheli, where her family said she had been well.
A theatre actress, she had studied musical theatre in New York and at the University of Arizona. She had recently played Juliet in her own production of Romeo and Juliet and was preparing to direct Oliver!.
Ms Lemos had also survived breast cancer, having been diagnosed in April 2023 and undergone six months of intensive chemotherapy. Following surgery, she spent four weeks in intensive care with haemophagocytic lymphohistiocytosis, a rare condition affecting the immune system.
“She had a whole life ahead of her,” her mother said. “She had so much more to give. And she should still be here.”
The Inner West London Coroner’s Court said the case remained under investigation. A UCLH spokesman said: “We were extremely sad to hear of the death of Marissa Lemos. We offer our deep condolences to her family and friends at this sad and difficult time.”
