For all the prestige of the classics, Royal Ascot remains the showcase fixture of British racing. Next week’s renewal promises a torrent of compelling themes, not least Finsceal Beo’s attempt to avenge her French 1,000 Guineas defeat by Darjina in the Coronation Stakes.

Then there is Frankie Dettori, who cannot throw himself aboard a horse without saturating it with confidence. However, a season dominated by human-interest stories will almost certainly yield to one about a horse. George Washington’s proposed return in the Queen Anne Stakes holds more than aficionados in thrall.

Everything about George Washington has been out of the ordinary. Europe’s most expensive yearling in 2004, Europe’s champion two-year-old in 2005, Europe’s champion three-year-old in 2006, and now, Europe’s most expensive stallion flop in 2007. All this from a horse who has only just turned four.

However, the best may be yet to come. After his abortive innings at stud, a triumphant return to racing would bring the house down. Ascot’s £200 million redevelopment could be reduced to rubble by acclaim for a horse with charisma to match his class.

Despite Coolmore’s disappointment over his sub-fertility, the fates have conspired to bring back an equine Cinderella whose Queen Elizabeth II Stakes triumph also served as his valediction. No sooner had he routed the best milers than realisation dawned that he was done with racing in Europe.

That was a glorious afternoon at Ascot nine months ago. Having polarised opinion throughout an injury-plagued season, George Washington united it emphatically with his strutting defeat of Araafa. But there could be no emotional send-off, no fond farewell for this supremely gifted racehorse.

Now he returns, although on significantly disadvantageous terms. Young male horses that cover mares undergo a mental change so profound that they are not asked to race simultaneously. Once introduced to sex, most think of little else.

Although O’Brien’s skills are legion, George Washington represents a new challenge. As much became clear on the horse’s return to Ballydoyle, when he took his rider for an unscheduled dip in a river. Having exercised in isolation for weeks, the horse was gradually reintroduced to the string. Ascot will reveal whether enough of George Washington’s mind has been retrieved for the purpose of recapturing former glories. It is not a forgone conclusion, particularly for one of his naturally fiery disposition.

There is good reason why stallions with fertility problems are the only ones to revisit the racetrack. Many do so to little or no avail.

There are exceptions, of course, but exceptions make the rule. This year’s winner of the Lincoln, Gentleman’s Deal, mixes racing with covering mares – albeit not in the same numbers as was required of George Washington. And Keltos, trained in France by Carlos Laffon-Parias, returned from an unproductive first year at stud to win the Lockinge Stakes five years ago.

Keltos resumed stallion duties with much-improved fertility. The sperm of young horses is sometimes compromised by nothing more than their physical immaturity, as may be true of George Washington. That will be established in the autumn, when he will cover some test mares.

In the meantime, Coolmore will be hoping that George Washington can emulate Radetzky, who returned from a fruitless stint at stud to land the Queen Anne Stakes in 1978. Trained by Clive Brittain, Radetzky prevailed at 25-1. Needless to say, nothing like those odds will be available about George Washington.

In normal circumstances it would be folly to expect too much. Yet the colt has so much going for him – raw ability, the collective brain of his connections, Ballydoyle’s master horsemen to re-educate him – that expectation swells in spite of events.