The theatre hit of the season in Melbourne is Mary Poppins. One of the hits of the show – and supercalifragilistic it certainly is – is "Anything Can Happen". It could have been written not for a stage musical about a magical nanny but for the fourth Test of a magical Ashes series which begins in the city on Boxing Day.
Such has been the dramatically changing nature of events so far it would be foolish to try to predict what might unfold over five days at Melbourne Cricket Ground. The feeling persists, however, as it has done since the tour began seven weeks ago, that if England do not win the Ashes in Australia this time they may never do so.
Never is a long time, not least in sport where things can change over an hour, but not so long that it can eradicate the five successive Ashes rubbers that England have lost in this country or the memory of losing the urn 18 times in 26 attempts since the start of the 20th century. There have been but four victories in the last 78 years and one of them was against a team merely masquerading as Australia.
If ever England needed reminding of just how hard it is to win a cricket series in this country that reminder was delivered in Perth last week. England, 1-0 up and cruising, were suddenly, sharply pegged back. A tour on which they were on the verge of taking all before them was in danger of having everything grabbed away.
But the result, defeat for England by 267 runs, did not establish Australia's superiority, it merely confirmed the closeness of the sides. Only two weeks previously England had won the second Test by an innings. It must be clear to the tourists that Australia have fallibilities to be exploited as it must be obvious to the home side that England have severe weaknesses.
"We're going to have the bit between our teeth this week," said Andrew Strauss, the England captain, yesterday. "We were all pretty disappointed with what happened at Perth and generally we've been good at coming back from poor performances. It's a good test for us and a massive occasion.
"It is going to be a great honour and pleasure to play on Boxing Day in front of that sort of crowd. But it means nothing unless we can go on and win the game. We've put Perth to bed, talked about that and we're very much focused on what could be a massive week."
A massive week indeed. If England win, they retain the Ashes, a feat they have not achieved in Australia since the last time they won here in 1986-87 when they also arrived as holders. But that knowledge did nothing to inspire them in Perth when England never recovered from a catastrophic hour in which they lost five wickets for 20 runs on the second morning.
"What we can be very happy with is that the vast majority of our play on tour has been good, consistent cricket," Strauss said. "We can afford to look at Perth as a bit of an aberration as long as we learn the lessons and don't repeat them."
They are bound to be scarred to a greater or lesser degree by Mitchell Johnson's ambush as they must pray that Graeme Swann, their spin bowler and ace card, will not be neutered as he virtually was in Brisbane and Perth. But the probability is that one will not again bowl as effectively and the other as ineffectively, at least not on the pitches to be provided at the MCG and at Sydney for the fifth Test next week.
England have not ruled out changes but have not ruled them in either. Paul Collingwood, around whom the vultures are gathering will play and probably still bat at five. This would be a measured response based on the team's balance but may not be the right one considering Ian Bell's form at six.
Strauss designated Collingwood's fighting qualities and reiterated that the team had great faith in him. "Ian Bell is in very good form and I can appreciate why people are clamouring for him to go up the order but I'm very happy with what he is doing down there. The main problem is that he has been left with the tail because there haven't been batsmen alongside him building big partnerships and that is our job." England will delay promoting Bell much longer at their peril. The teams are few whose best batsman comes in at No 6.
If there is a player at risk, it is Steve Finn. Although Strauss insisted there would not be a change in personnel to try solely to deal with the threat of Mike Hussey, who has scored 517 runs in the series, Finn has not found a regular length to suit each pitch.
"I think he's been a little frustrated that he hasn't been as consistent as he would like. Last summer in England, his lengths were very good consistently and maybe he has not done it on this tour. But he is a bowler with a knack of taking wickets, a great skill to have. Every match he plays he is learning about bowling in Australia. The vast majority of what he has done on this tour I've been very happy with and I expect him to continue getting better.
"It has been a demanding Test series especially with four bowlers, three seamers, and Stuart Broad didn't bowl in the second innings at Adelaide. So the bowlers have had quite a lot on their shoulders but I don't think that's a reason for him not to play." Interpreting Strauss's comments about selection may be testing at times but Finn might be kept waiting for his 12th Test cap.
For England to win they probably need two things to happen: a first innings score in excess of 300, which they have so far failed to accrue in two of the three Tests, which would, in turn, give Swann something to work with.
As Mary Poppins sings, without having Swann in mind as it happens: "If you reach for the stars all you get are the stars but we've found a whole new spin, if you reach for the heavens you get the stars thrown in." Anything can happen and probably will.