Britain's King Charles III, whose cancer diagnosis was announced on Monday, has thrown himself into the role of monarch since ascending to the throne nearly 17 months ago.
At an age when most people are retired, Charles, now 75, began the job he was born to do in September 2022 upon the death of Queen Elizabeth II.
Unlike Elizabeth, who cultivated an air of mystery and distance, Charles has shown himself to be much more accessible, at ease smiling and shaking hands with crowds at public events.
During a lifetime spent as heir, Charles -- who has said he remains "wholly positive" about his cancer diagnosis -- cultivated a range of interests and passion, from architecture to organic farming.
He also led the way as an early advocate of environmental and climate issues.
Seen as a lovable eccentric by some -- he once famously admitted to talking to his plants -- others have remained critical of his messy divorce from Princess Diana, whose popularity eclipsed his own and whose death in a car crash in 1997 led to a crisis for the monarchy.
Since becoming king he has been a visible presence in all four nations of the United Kingdom, heading a push for unity after a turbulent recent past marked by Brexit and calls for Scottish independence.
Charles has been notably open about the state of his health.
Last month it was announced that he had an enlarged prostate and would undergo a procedure in hospital, though the condition was not cancerous.
That disclosure prompted a surge in internet searches for the term "enlarged prostate" on the state-run National Health Service (NHS) website.
Buckingham Palace said the king had wanted to be open about his subsequent cancer diagnosis to "prevent speculation and in the hope it may assist public understanding for all those around the world who are affected by cancer".
That chimes with his desire for a more modern, open monarchy that keeps the ancient institution relevant, particularly to younger Britons, and as republican sentiment mounts in the 14 other countries outside the UK where he is also king.
Charles also heads the 56-nation Commonwealth grouping, which comprises about a quarter of the world's population.
He has called for unity there, too, to help tackle "the most pressing issues of our time", including climate change.
- Overshadowed -
Charles lived for 70 years in his mother's shadow, with his only role as heir to support her "as a focal point for national pride, unity and allegiance".
But despite his obvious enthusiasm for his new job, tensions with his youngest son Harry and his wife Meghan have blighted the start of his reign.
Harry's score-settling in his autobiography "Spare" and a Netflix series grabbed headlines just as Charles had been seeking to make his mark as monarch.
Despite the cheering crowds that turned out for his coronation last May, not everyone has welcomed him with open arms.
Some royal walkabouts have seen anti-monarchy protests, including egg-throwing.
On the popularity front, Charles (51 percent) lags behind his mother (75 percent) and William (68 percent), according to the latest surveys by pollsters YouGov.
Royal commentator Richard Fitzwilliams, however, described his ratings as "not too bad at all".
"If someone ascends to the throne in his seventies, you will get respectable ratings, and he has because he is conscientious," he told AFP.
Peter Ricketts, the UK's former ambassador to Paris, said that he believed Charles would be respected for bringing his "personal convictions to the job", not least about the importance of saving the planet for succeeding generations.
- Doting grandfather -
Ricketts described Charles as a "warm, emotional man", while William and Harry have said he is a hardworking father who they often found asleep in his office late at night.
Queen Camilla, Charles's second wife, has described her husband as a man a hurry but also a doting grandfather who reads his grandchildren Harry Potter books.
"He does all the voices because he's a brilliant mimic," she has said. "It's really sweet. He's extremely good with children. They love it."
With Harry self-exiled in the United States, and Charles's younger brother Prince Andrew sidelined after a sex scandal, the king has been building the monarchy around himself and Camilla.
William and his wife Kate are also part of the inner circle, with the king's youngest brother Prince Edward and his wife Sophie.
The wisdom of Charles's so called "slimmed down" monarchy, however, was questioned last month after it was announced that Catherine, the Princess of Wales, was to have abdominal surgery requiring weeks of recuperation.
With Charles out of action for his prostate procedure and Catherine's husband -- heir to the throne Prine William -- stepping back to help look after their family, the most visible frontline royal was 76-year-old Camilla.