The daughter of Dubai's ruler who tried to flee the country in 2018 later sent secret video messages to friends accusing her father of holding her "hostage" as she feared for her life.
In footage shared with BBC Panorama, Princess Latifa Al Maktoum says commandos drugged her as she fled by boat and flew her back to detention.
The secret messages have stopped - and friends are urging the UN to step in.
Dubai and the UAE have previously said she is safe in the care of her family.
Ex-UN rights envoy Mary Robinson, who had described Latifa as a "troubled young woman" after meeting her in 2018, now says she was "horribly tricked" by the princess's family.
The former UN High Commissioner for Human Rights and president of Ireland has joined calls for international action to establish Latifa's current condition and whereabouts.
"I continue to be very worried about Latifa. Things have moved on. And so I think it should be investigated," she said.
Latifa's father, Sheikh Mohammed bin Rashid Al Maktoum, is one of the richest heads of state in the world, the ruler of Dubai, and vice-president of the United Arab Emirates (UAE).
The videos were recorded over several months on a phone Latifa was secretly given about a year after her capture and return to Dubai.
She recorded them in a bathroom as it had the only door she could lock.
