Bookmakers are praying the Grand National's propensity to pen fairytale storylines will not result in Tony McCoy heading off into retirement after success with Shutthefrontdoor on Saturday.
McCoy, in the final furlong of his spectacular career, says he will hang up his irons a fortnight early should the Jonjo O'Neill-trained contender do the business at Aintree on Saturday.
Shutthefrontdoor is forecast to start the shortest-priced favourite since Red Rum (7-2 in 1975) to supply McCoy with the perfect send off after two decades at the peak of his profession.
The McCoy factor has inevitably dominated build-up to the gruelling world famous four-and-a-half mile steeplechase first run in 1839.
A second National triumph for McCoy could cost the betting industry tens of millions of pounds, British media reported this week with bookmakers' share prices taking a hit.
The thought of bookies cancelling holidays in the Caribbean for a weekend's caravaning in Cornwall will hardly have punters' reaching for a box of tissues to wipe away their tears.
Shutthefrontdoor, last year's Irish National winner, currently heads the ante-post market at 7-1 - the same odds as Comply or Die when he won in 2008.
But the bundles of cash expected for McCoy's mount could see it set a new record for the modern era - forecasts from William Hill and Ladbrokes suggest up to a third of the £300 million ($443m) wagered on the race will be for McCoy.
"Shutthefrontdoor has been backed off the boards for over a month and the gamble shows no signs of slowing," Betfred spokesman Andrew Griffiths said this week.
"The McCoy factor is driving the odds down all the time so it would be folly to rule out a starting price of less than 7-2."
The 40-year-old McCoy told the Liverpool Echo: "Looking at the betting, the bookmakers seem to think it is going to happen and hopefully they are right.
“Shutthefrontdoor won the Irish National and has not run since winning at Carlisle in November.
"I am sorry for all the failures I have had in the Grand National over the years and this will be the last time I let anybody down but hopefully I will go out on a high and shut the front door behind me!"
This year's renewal of the race that like Australia's Melbourne Cup stops a nation features 2014's unlikely hero Pineau de Re seeking to become the first back-to-back winner since Red Rum in 1974.
Former GP Richard Newlands's charge sprang a 25-1 surprise 12 months ago, and is similarly priced for a repeat after a lowkey buildup.
"I am not downbeat at all - we are carrying 11st and we have serious grounds for optimism," Newlands said.
Richard Johnson, who has finished second to McCoy in the jockey's title race 15 times, partners last year's second Balthazar King.
Johnson has joked that beating his old rival who has his 20th jockeys' championship in the bag by a short head on Saturday would be "the perfect result".
No woman has ever won the race watched by an estimated 500 million viewers across the globe - Katie Walsh came closest when third on Seabass in 2012.
Her sister-in-law, Nina Carberry, is seeking to put that right on 33-1 shot First Lieutenant.
Carberry is 13 years older than Sean Bowen who at 17 is attempting to become the youngest winning rider in 77 years. The teenager teams up with Mon Parrain.
The latter is one of four contenders trained by Paul Nicholls who has a more obvious chance with joint second favourite Rocky Creek, a recent scorer at Kempton.
Willie Mullins saddled a record eight winners at last month's Cheltenham festival, but if the betting is any guide looks to have only an outside hope with his lone raider, Ballcasey.
The burdensome task of lumping topweight of 11st 10lb falls on the shoulders of 2014 Cheltenham Gold Cup winner Lord Windermere, a 40-1 shot.
As the annual date with Becher's Brook, the Canal Turn and the Chair - looms, McCoy more than anyone appreciates there is no divine right to winning the National.
He finally cracked the Aintree puzzle at the 15th attempt in 2010 on Don't Push It, trained by O'Neill and owned like Shutthefrontdoor by his stalwart supporter, JP McManus.
"I have dreamt a lot in my life but I would not be silly enough to dream about winning the National again," he says.
McCy's dream is the bookies' nightmare.
Source: AFP