Film star Hugh Grant, "Harry Potter" author J.K. Rowling, and the father of missing girl Madeleine McCann are among those due to testify over the next week at the U.K. inquiry into media ethics - a judicial body that could recommend sweeping changes to the way Britons get their news.
The nationally televised inquiry would give many of those in the public eye an unprecedented chance to challenge those who write about them, said Cary Cooper, a professor at northern England's Lancaster University and the author of "Public Faces, Private Lives."
"This is the first time the celebrities have been able to strike back," Cooper said. "I think it will have an impact, and the media might - for a while at least - pull away."
Speaking ahead of the testimony, victims' lawyer David Sherborne told the inquiry multiple tales of shattered privacy, broken lives and even suicides stemming from relentless media intrusion.
"When people talk of public interest in exposing the private lives of well-known people or those close to them, this is the real, brutally real impact which this kind of journalism has," Sherborne said.
Britain's media ethics probe was set up in the wake of the scandal over phone hacking at Rupert Murdoch's News of the World, which was shut in July after it became clear that the tabloid had systematically broken the law. Most horrific was the news that the tabloid had broken into the phone of murdered schoolgirl Milly Dowler in its search for scoops.
Cooper acknowledged that celebrities like Grant or actress Sienna Miller - another star due to give evidence - have struggled to get much in the way of public sympathy even when it was shown that their privacy had been invaded. But he said their appearance alongside crime victims such as Bob and Sally Dowler or Gerry McCann could mark a shift in attitudes.
"They're going to get hit worse by the Milly Dowler family and witnesses of that ilk," he said.
Sherborne, in a two-and-half-hour-long presentation Wednesday, promised to make journalists squirm.
Most powerful among his accusations was the suggestion that media coverage had driven some celebrities' family members to the brink of suicide - or beyond.
Sherborne said that former Formula One racing boss Max Mosley believed that the suicide of his 39-year-old son Alexander could also be at least in part attributed to "the very public humiliation" dealt to his father by the News of the World's expose of his sexual shenanigans.
He went on to outline the case of soccer player Garry Flitcroft, whose life was turned upside down by a newspaper's revelation that he'd cheated on his wife. Flitcroft's children were teased in school, his family was tracked by helicopter and his ailing father fell into a deepening depression before taking his own life, the lawyer said.
Another case involved Charlotte Church, the British singer who shot to stardom as a teenager. Sherborne said she'd been subjected to waves of harassment. Photographers chased her in cars, tried to take pictures up her skirt and cut holes in bushes to install secret cameras. So hungry was the press for scoops about her private life that journalists revealed she was pregnant before she had even told her parents.
Worse still was the News of the World's expose of her father's affair in 2005. Sherborne said that Church's mother had attempted suicide shortly before the story ran, but that rather than hold back, "the newspaper approached her mother directly and persuaded her to give them an exclusive, despite her fragile condition, as part of a Faustian pact that in return they would not run another lurid follow-up story about her husband's affair."
Others testifying over the next seven days include comic actor Steve Coogan, whose romantic exploits have been exhaustively documented, and broadcaster Anne Diamond, who was targeted by Murdoch's press after she challenged the mogul about his ethics.
Chris Jeffries, who was wrongly implicated in the murder of his tenant, is also due to give evidence, along with soccer star Paul Gascoigne's ex-wife Sheryl; human rights activist Jane Winter; former army intelligence officer Ian Hurst; and Margaret Watson, whose teenage daughter Diane was stabbed to death in 1991.
The Leveson Inquiry: http://www.levesoninquiry.org.uk/