By Neil Smith
Entertainment reporter, BBC News
Daniel Craig's casting as the new 007 marks a pivotal moment in the James Bond franchise.
It will determine whether Her Majesty's best-known secret service agent has a future in the 21st Century, or whether he is destined to become a much-loved relic of Britain's cinema past.
Speaking on Friday at his official unveiling, Craig said the strength of the 007 series is that it "redefines itself and is always of its time".
But with three years since Bond's last outing and younger, fresher rivals snapping at his heels, only time will tell if this latest revamp will succeed.
Thanks in no small part to the iconic presence of Sean Connery, James Bond was a 60s phenomenon.
The premiere of Goldfinger in 1964 almost caused a riot in London's Leicester Square, while the character's impact was felt across the globe - not least in the number of shameless imitations it inspired.
But for producers Harry Saltzman and Albert R Broccoli, Connery's indelible association with the role was as much a headache as a boon.
Their first attempt to recast the part, with George Lazenby in 1969's On Her Majesty's Secret Service, was a disaster, forcing them to woo Connery back to the franchise for a $1.25m paycheque.
Bringing in an established star like Roger Moore in the 1970s enabled the series to continue, though it took three outings for the actor to enjoy the same success as his predecessor.
Brosnan made four Bond films, including The World Is Not Enough
But his advancing years - almost comically apparent in 1985's A View to a Kill, made when he was 58 - forced "Cubby" Broccoli to seek a younger actor to propel the series into the next decade.
Timothy Dalton proved a virile choice with a performance that took much of its inspiration from Ian Fleming's original books.
But audiences did not warm to the actor in either of his two outings, while the series looked increasingly dated beside the new breed of action blockbusters emerging from Hollywood.
Licence to Kill in 1989 was trounced at the box office by Batman and Lethal Weapon 2, forcing Bond producers Eon to initiate a comprehensive rethink of the series.
This coincided with a lengthy court battle with MGM over the ownership of the character, meaning it was six years before 007 returned in 1995's Goldeneye.
The film's huge success proved there was still a market for the Bond brand, with Pierce Brosnan emerging as a crowd-pleasing natural as the debonair hero.
But while the Brosnan Bonds paid lip service to prevailing trends - making "M" a woman for example, or setting the action in a post-Cold War landscape - their appeal was primarily a nostalgic one.
Younger, hipper secret agents, from Vin Diesel's XXX to Matt Damon's Jason Bourne, were starting to make the character look his age.
And the films' ostentatious use of product placement - with Bond promoting everything from BMW motorbikes to Omega watches - gave critics another stick to beat them with.
Then there were the gadgets. In the early days, the gizmos Bond received from Q-Branch - like the primitive GPS tracking system featured in Goldfinger, or the "Little Nellie" autogyro in You Only Live Twice - were a fascinating insight into nascent technology.
Damon's Jason Bourne films have been compared with Bond movies
In 2002, however, his invisible car was greeted with derision, suggesting the producers had finally strayed too far into the realm of absurdity.
Director Martin Campbell's insistence that the 21st film, Casino Royale, will have "more character and less gadgets" sounds an encouraging note.
But seasoned Bond watchers will recall similar claims being made before Dalton's first outing, and Brosnan's as well.
Clearly the 007 producers feel a younger, back-to-basics Bond is required to ensure the series can survive and flourish.
However, they would do well to remember another recent film franchise that tried a similar tactic with little success.
After one Jack Ryan thriller starring Alec Baldwin and two more with Harrison Ford, the decision was made to continue the series with a younger actor in the role.
Unfortunately, that actor was Ben Affleck, whose celeritous fall from public favour took the Tom Clancy spy franchise with him.