Wednesday's transmission of an ITV film, Charles: the Private Man, the Public Role, is effectively a re-launch of the Prince on the 25th anniversary of his investiture.
It will attempt to redefine his profile as heir to the throne. It may even suggest that despite what Charles has lost - his wife, and his patience with the hand Providence has dealt him - he has not lost his way.
The two-and-a-half-hour programme is largely the work of Jonathan Dimbleby, a distinguished television journalist noted for his probing mind, liberal social conscience and disinclination to kowtow to the Establishment. Its presentation comes at a time of serious divisions over Prince Charles: in Buckingham Palace over the way his children are being raised; in the Church over his worthiness to make coronation vows if he broke his marriage vows; and among his future subjects over the publicity wars attending royal events.
But should the film fail to restore the princely profile, it may be to the detriment of the presenter as well as of the Prince. A recent Spectator article claims that friends of Dimbleby are worried about 'how he is going to come out of all this. The suspicion is that he will simply end up a pawn in the publicity game.'
Diana, on the other hand, might win the game hands down.
The Princess of Wales has not seen the film and will not be watching on Wednesday, according to her Palace press secretary, Geoff Crawford, having chosen instead to attend a gala dinner at London's Serpentine Gallery, organised by the American magazine Vanity Fair. Mr Crawford was unable to say if she would later view a video-tape of Prince Charles's triumph. (He is said to be 'thrilled' with the edited result). On past form, however, it would be surprising if the Princess did not try to trump his performance yet again.
At first glance, the Prince is ahead on public relations expertise. With the Palace press office pretty well behind him, he can also rely on another group, known as The Friends of the Prince and including the Food Minister, Nicholas Soames, and Lord Romsey, a member of the Mountbatten family, to muster support for the princely cause.
Charles leans heavily on Allan Percival, one of the few streetwise operators in the Palace press office (he used to be with the Northern Ireland Office), on his private secretary Richard Aylard, and on Belinda Harley, a public relations adviser, three of a nine-strong private office.
The Princess appears to be less well served. For emollient statements, neither Geoff Crawford nor her private secretary, Patrick Jefferson, can be faulted. The Prince and Princess, says the former, 'have complementary, rather than competing programmes'. But Anthony Holden, a biographer of Prince Charles, argues that they do not enjoy her complete confidence 'because they're answerable to Charles Anson', the Queen's press secretary. Princess Diana, he says, 'relies on shrewd PR instincts of her own'. Consequently, a few well- chosen newspaper reporters are in occasional receipt of a few well-chosen royal scoops.
One of the recipients is Richard Kay of the Daily Mail. With eight days to go before transmission of Charles: the Private Man, the Public Role, Mr Kay produced a front-page exclusive about a 'secret' visit by the Princess and her sons, Prince William and Prince Harry, to a hostel for the homeless. The visit, he wrote, was 'significant' for sartorial contrast: the princes and their mother in humble jeans at the hostel, while Prince Charles was being photographed at Ascot 'wearing top hat and tails as he mingled with high-society friends'.
The Princess is said to have 'particularly good connections' with Mr Kay. 'He's a nice chap, slightly up-market and ex-public school,' says Richard Tomlinson, author of a forthcoming book (Divine Right: the inglorious survival of British royalty). Mr Kay, who modestly identifies his public school as 'Ipswich, a very minor one', is hesitant about talking to other newspapers. But he believes the Princess 'is winning the PR war, because she's young, glamorous, attractive and, for all her faults, the one about whom most British people wish to read'. As for the suggestion that certain journalists have become royal conduits, he says: 'Take it from me, these stories are not delivered to us, and we're not served them up. We have to get them. But at the same time, particularly over the last two years there has been increased manoeuvring by the two sides to try to present their royal clients in the best possible light. This never happened in the past.'
Diana has an advantage in not planning her engagements as far ahead as does Charles, so she has room for impulsive moves that may put his public appearances in the shade. 'There's no question she enjoys trumping Charles,' Mr Tomlinson says.
Her current activities suggest he may be right. She is, for example, on the cover of the July issue of Vogue. Last week, following her visit to the homeless, she made a very public exit from a party at the Ritz, standing in the street in a slinky new dress, with excited photographers all around. The result was another sartorial contrast; 'sexy' Di outshining 'strait- laced' Charles in kilt and jumper when stills from the film were distributed.
Few of the myriad royal biographers have failed to notice. 'She has declared open warfare on Charles,' says Penny Junor. 'This is meant to be Charles's year,' says Brian Hoey. 'Other members of the Royal family have deliberately played down their roles. But Diana is doing exactly the opposite.' A third biographer, Lady Colin Campbell, agrees. 'Nobody who wants to keep a low profile buys a sexy new dress . . . then goes off to a lavish party at one of the world's most famous hotels.'
'Charles's Year' began immediately after Diana's announcement last December that she was withdrawing from public life. During it, the Prince of Wales has been praised for his stoicism when shot at by a deranged man in Australia, while the Princess of Wales was praised for her 'dramatic rescue' of a drowning tramp in Regent's Park. He went to St Petersburg shortly after it became known she was planning a visit to Moscow (but did not go in the end). Press references to the cost of his 1994 peregrinations - accompanied by equerry, doctor, driver, private secretary, press secretary and bodyguard - were followed by disclosures about her expenditure on clothing and hair-dos.
Public responses to the Dimbleby film may not bring this PR conflict to a head; they could conceivably exacerbate it. 'We are all wondering if key questions will be asked on the programme,' Mr Kay says. 'They revolve around Charles's marriage, his estranged wife and his so-called affair. If those aren't dealt with, then we're going to feel hard done by and we're all going to say it's a lot of old snow.'
The Prince has had such difficulties for years. As Richard Tomlinson points out: 'There's always been a problem with Charles, in that he actually won't play ball. He wants to be judged by what he does, and doesn't want to pander to the press.'
Richard Aylard is credited with forcing the Prince 'not to hide his light under a bushel.' But Mr Tomlinson believes the Princess's knack of attracting publicity is also a force in the same direction. To counter the Diana machine, he will have to perfect the design of his own. 'In the end, Diana will not prevent him from being king,' he says.
Anthony Holden is less sanguine, pointing to 'an extraordinary upsurge' in support for the British republican movement. 'There is a section of the press, including the Daily Telegraph and Daily Express, who are in the Prince's party. There is also a section of the press which recognises someone its readers admire; someone deceived by her husband and treated badly by his family.
'Charles has lost almost every section of society. Diana is winning by a mile. The Dimbleby film is do-or-die for Charles.'