Once upon a time, reverse swing was a dark, nefarious art, practised by Johnny Foreigner on upright, unsuspecting Englishmen.
Today it is a magical, miraculous gift, totally above board, practised by upright Englishmen (or one upright Englishman and one Welshman, to be more accurate) and which might yet decide the outcome of the 2005 Ashes.
Reverse swing -- the ability to swing an old cricket ball in the opposite direction to that expected by batsmen -- has been around for decades.
It has not, however, had as great an impact as it is having on the current series between England and Australia for a long while.
Back in 1992, Pakistan fast bowler Waqar Younis made the old ball reverse in, viciously fast, viciously late and invariably on a yorker length. Often it broke a stump or broke a toe.
Waqar did not make the ball swing away but it did not much matter. England's batsmen knew where the ball was going but could do little about it.
Nor could they begin to understand how Waqar and Wasim Akram were managing to make the ball boomerang around corners.
The conviction grew that it was all done illegally, with bottle tops and penknives and sharp fingernails. Reverse swing became a synonym for ball tampering.
Emotions became so heated that players and former players from both sides even found themselves facing each other in British libel courts.
Those legal confrontations helped uncover some of the mystery.
Sarfraz Nawaz, another hugely gifted Pakistan fast bowler, revealed how he had discovered the phenomenon in the 1970s.
First he would swing the ball traditionally, the seam upright to act as a rudder and one side kept shiny to make it go through the air quicker.
Then, when the ball aged, he would apply sweat to the shiny side, weighing it down, while leaving the other dry and rough. Using the outwsinger's grip, he could create inswing.
The magic passed from Sarfraz to Imran Khan to Waqar and Wasim and England were well beaten on home turf in both 1992 and 1996.
Even when the rest of the world discovered the secret, however, they found out that know-how mattered less than can-do.
Every bowler seems to understand reverse swing but few can make it happen.
Today, England have unearthed two men who make it happen with alarming regularity.
Simon Jones, a one-time team mate of Waqar's at Glamorgan, and Andrew Flintoff, have even added a new dimension.
NO BOTTLE TOPS
Both can make the old ball swing into batsmen but they can also make it swing away. They are also reverse swinging the ball much earlier in an innings than previously seen, after around 15 overs rather than 40.
No bottle tops, raised seams or unexplained marks on the ball have been spotted, leading to suggestions that England's big fast bowlers, the hard grounds and the habit of their fielders of throwing the ball in on the bounce rather than on the full, have helped to rough up the ball more quickly.
Australia's top-order batsmen have certainly been clueless while Jones and Flintoff have swung the ball as if by remote control.
At Old Trafford, Jones sent down a couple of outswingers to Michael Clarke. The next ball was well wide and Clarke shouldered arms. The ball banana-ed into his off stump.
"It's like a new little puzzle we have to solve," Australia opening batsman Justin Langer said.
"All of a sudden, rather than being instinctive with your batting, where you just can see the ball out of the bowler's hand and you can just go with your shots, you've got to watch it that little bit closer...you tend to tighten up."
Some of the recent British press coverage, captivated with England's unexpected successes against Australia in the last few weeks, seems to have forgotten the 1990s altogether. Waqar, watching from afar, cannot help a wry smile.
The Pakistani, who retired last year, says reverse swing has been given a positive spin in the last few weeks.
"It is being given a new name now," he said.
"When we bowled it, it was called ball tampering. Now that they have somebody to do it, bowlers like Flintoff and Jones, they are coming up with new words to glorify it."