Marrying an American, singing pop songs on talent shows, roles in movies and posts on Instagram, Princess Ubolratana has long broken the mould of Thailand's royal family -- but her entry into politics is her boldest move yet.
The elder sister of Thailand's King Vajiralongkorn was only 21-years-old when she confirmed her status as the rebel of the family, an institution steeped in arcane tradition and fiercely shielded by a harsh lese majeste law.
In 1972 she renounced her royal titles to marry Peter Jensen, an American she had met while studying mathematics at the prestigious Massachusetts Institute of Technology.
She lived a comparative commoner's existence in the United States, where she was known as Julie Jensen, for more than quarter of a century before their marriage broke down.
Ubolratana returned to her homeland where she was embraced by her family, treated as a senior royal once more and afforded the wealth and trappings of her re-acquired station.
The monarchy is considered sacred and above reproach in Thailand. Roads are routinely cleared for royal convoys and senior members attend events surrounded by courtiers and cloaked in strict palace protocols.
But while Ubolratana is afforded the same privileges, the 67-year-old princess has cultivated a more accessible image than her reserved younger brother and shown a knack for reading the sentiments of ordinary Thais.
When crowds gathered for days in huge numbers outside the Grand Palace following the death of the late King Bhumibol Adulyadej in 2016, Ubolratana was the first senior royal to greet the mourners, distributing food and thanking well-wishers in footage that swiftly went viral.
In a institution that leans heavily on protocol and tradition, she has embraced pop culture and the spotlight.
Last year the princess played the role of popstar, performing onstage a song popularised by Thai girl group BNK48.
In 2008 she starred in a movie, "Where the Miracle Happens", which opened in Cannes, and played a journalist in her second film foray in an action-packed thriller featuring explosions, gunfights and car chases.
- Political leanings? -
Her frequent social media posts range from celebrating Chinese New Year and celebrating her favoured charity causes to addressing the everyday problems that Bangkokians face -- most recently the toxic smog that has been shrouding the city.
"This problem must be solved as soon as possible -- the kids cannot go to school anymore," she wrote under a post of her wearing a black pollution face mask.
"I'm trying to study what can be done because we all are going to get worse."
She also experienced first hand the tragedy of the huge 2004 Asian tsunami -- her autistic son Poom was one of more than 5,000 people killed by the waves in Thailand.
While Thailand's monarchy portrays itself as officially above the political fray, its senior members have in the past chosen to intervene during key moments of crisis.
Ubolratana had never shown an overt interest in politics, but there have been clues that her sympathies may have rested with the powerful Shinawatra dynasty -- who are beloved by Thailand's rural and urban poor but loathed by Bangkok's military and royalist elite.
Former prime ministers Thaksin and Yingluck Shinawatra both now live overseas after fleeing what they say are politically motivated charges following coups that toppled their governments.
Ubolratana was spotted with Shinawatras attending a World Cup football match last year.
And she also endorsed a tweet by Thaksin that slammed "tyranny" by quoting the French thinker Charles de Montesquieu.
Underneath she wrote "I agree, su su!" (fight, fight).
Her latest Instagram post on Thursday set tongues wagging as rumours swirled that she had agreed to stand as a prime ministerial candidate for a Thaksin-linked party at the upcoming general election in March.
In it Ubolratana was all smiles, holding a red flowers and wearing a traditional dress from northern Thailand.
In a country where people are adept at reading subtle political cues, the signal was clear: the Shinawatras' heartland is Thailand's north and their political colours are red.