If Martin O'Neill was to think too deeply about Aston Villa's defensive situation, he would develop a piercing headache.
As a story, it has more sub-plots and characters sketches than the average Somerset Maugham novel and there is not even the guarantee of an edifying denouement.
Worse still, there is no knowing when or how the story started.
Did it start when Olof Mellberg, Villa's most assured defender over the past six years, stalled on signing a new contract? Did it start when Gary Cahill, the most promising of Villa's younger defenders, was sent out on loan to Sheffield United? Did it start when Curtis Davies joined Villa in August but found himself on the periphery? Or did it start when Martin Laursen expressed concerns about his own future?
Whatever, O'Neill knows that the managerial skills for which he is famed, the skills that nearly gave him the job as England head coach, will be required like never before as he bids to stabilise a defence that has, overall, performed well this season.
Mellberg appears to be off. He has dropped the strongest of hints that he might be moving to Juventus in the summer, by which time he will be out of contract and at liberty to leave on a free transfer.
There are rumours that Liverpool, themselves desperate for defenders, are believed to be looking to try to sign the player - for a fee - when the January transfer window opens in 18 days' time.
Laursen, one of Villa's best players this season, is also out of contract at the end of the season and has previously been linked with a move to Tottenham Hotspur.
Laursen, the Denmark international, has suggested that Villa are "delaying" offering him a new contract and are "playing a dangerous game" - viewpoints refuted by O'Neill.
The situation concerning Cahill is equally unclear. When he burst on to the scene with Villa in 2000-06, aged just 19, he was rightly seen as a future England international.
Now on loan with Sheffield United, where he has developed a strong sense of his own identity, he is making the appropriate improvements to his game.
Bryan Robson, the Sheffield United manager, wants to keep Cahill on a permanent basis but probably knows that Villa would never countenance such a suggestion.
An extension to Cahill's loan period is more likely because the defender is still seen as being part of O'Neill's plans. If Mellberg and Laursen leave, it seems likely that Cahill will return to Villa Park.
What this all means for Davies remains to be seen. Signed initially on loan from West Bromwich Albion, with a view to completing a £10 million permanent move, Davies has been forced to bide his time and familiarise himself with reserve-team football.
When he made his Villa debut, against Leicester City in the League Cup in September, he described his own performance as that of "a pub-team player".
His honesty endeared him to the majority of Villa supporters and now, having shown an attitude that has endeared him to O'Neill, Davies seems on the verge of a recall to the starting line-up.
In a fantasy world - not the Somerset Maugham world, which is too much like bleak reality - Davies and Cahill is Villa's central-defensive partnership of the future. Both are still in their early-20s and are not expected to hit their peak for another five years.
It could be that, even if Mellberg and Laursen did remain at Villa Park, they would do so on short-term contracts with a view to leaving once Cahill and Davies (individually and as a partnership) were of the required standard.
For now, however, there is the domineering figure of Zat Knight.
Bought from Fulham to replace Liam Ridgewell, who moved to Birmingham City, Knight is slowly but surely emerging as a competent and enthusiastic stopper; just the type that Villa lacked throughout the David O'Leary era.
But O'Neill still needs to scour the transfer market for at least two new centre backs, just in case Mellberg and Laursen do leave.
Sami Hyypia, of Liverpool, was deemed to be available as a stop-gap but that was before Liverpool suffered the loss to injury of Daniel Agger.
Fernando Meira, the Portugal international defender, could have been a possibility until he decided that he wanted to remain with Stuttgart in Germany.
One can be sure that O'Neill is aware of every available centre half in Britain and Europe but his needs go deeper than that.
He also needs to sign a specialist right back, which rather emphasises the problems that Mellberg's probable departure will cause.
Mellberg has been filling in at right back this season, usually to good effect, and can read a game better than most players in the Premier League.
However, since Mark Delaney retired through injury, Aaron Hughes was sold by O'Neill to Fulham last summer and Villa decided against signing Phil Bardsley from Manchester United on a long-term basis, the lack of specialist right backs has been a significant feature of life at Villa Park.
Mellberg is a significant link with the past; a man signed by John Gregory for £5.5 million in August 2001 and worth every penny. Mellberg was there when Villa reached the top of the Premier League in late-October 2001, when his central-defensive partnership with Alpay Ozalan - remember him? - briefly looked world class.
"Juve?" Mellberg said, when the matter was raised by a journalist from Tuttosport of Italy. "I cannot deny it."
