By Wednesday afternoon Tony Blair may look like one of those gravity-defying superheroes - "with one bound he was free" - or he may be a damaged leader, limping on without a solid parliamentary base. At worst, the Prime Minister could find himself in the untenable position of having Lord Hutton question his honesty.

The drama will begin at noon on Tuesday out of the public eye, when a squad of messengers arrives simultaneously at six locations, bearing advance copies of Lord Hutton's bulky report. For some of the people allowed to read these early copies, under tightly regulated conditions, Lord Hutton's words could make the difference between vindication and ruin. For the small number of Downing Street officials on the approved list, the big question will be what the report says about Tony Blair.

However quickly they read it, they will probably not be quick enough to relay the news to the Prime Minister before his first public appearance of the day. The debate on the vulnerable Higher Education Bill will kick off in the Commons at 12.30pm, with an opening speech by Charles Clarke. Mr Blair will want to be at the side of his Secretary of State for Education as Mr Clarke battles for the last time to convince a rowdy, divided House that variable tuition fees are the right way to fund universities.

After an hour or so, Mr Blair will slip away to his room behind the Speaker's Chair, where his staff will be ready to give him the good or the bad news about the Hutton report.

Meanwhile, the debate in the Commons will plough on, pitching Labour MP against Labour MP. Outside the debating chamber government whips will be on the prowl, checking the whereabouts of every MP and making last efforts to win over any waverers.

At 7pm, after a winding-up speech from the Higher Education minister Alan Johnson, MPs will vote. Expect pandemonium to break out when the result is announced about a quarter of an hour later, with wild cheering from the winners and scowls from the losers.

The last time a government was defeated in the Commons, over the Maastricht Treaty, the Prime Minister himself - John Major - immediately announced he was calling a vote of confidence the next day. Mr Blair's position is not as precarious as Mr Major's was then, but he may have no choice but to follow that precedent. If he does not call a confidence vote, Michael Howard may call him a chicken and force one on him.

It will be a short night's sleep for Mr Howard, because he and a fellow Tory, David Cameron, will be at the Cabinet Office by 6am, to be locked in a secure room to read the Hutton report. Charles Kennedy and the Liberal Democrat foreign affairs spokesman Menzies Campbell will be locked in another room.

They will emerge a little under six hours later to rush to the Commons for Prime Minister's Questions. As things are now scheduled, noon on Wednesday will see mayhem in the Commons, with MPs crowding around the vote office in the lobby to be the first to grab copies of the Hutton report when it is officially published, at exactly the moment when Prime Minister's Questions begins. The broadcasters will also have to choose which live drama to follow - the exchanges in the Commons, or Lord Hutton's statement in Court 76 of the Royal Courts of Justice a mile away.

Mr Howard and Mr Kennedy, meanwhile, will be spoilt for the choice of questions they can fire at Mr Blair. They could concentrate on the Hutton report, which they will have read, or save that battle until later, focusing instead on tuition fees, or the lack of weapons of mass destruction found in Iraq.

Mr Blair will make a statement to the Commons on the report as soon as Lord Hutton has completed his announcement. He will want to do this as soon as PMQs finish, at 12.30pm, but there may be a hiatus if Lord Hutton is still speaking at the court then. The chaos will be eased if Lord Hutton decides to bring the moment of publication forward to 11.30am.

Because the Prime Minister is making a formal statement, Mr Howard and others will theoretically have to restrict themselves to asking questions of Mr Blair - though Mr Howard's "question" will be along the lines of "isn't it the case that the Prime Minister lied?". The formal debate and vote on the Hutton report will be on 4 February.

The excitement will recede by about 2pm as MPs discuss the National Insurance Contributions and Statutory Payments Bill. If there is a vote of confidence in the Government, it is likely to be on Thursday. Tony Blair will win handsomely as the Labour Party closes ranks behind him. To those who have wondered whether Mr Blair will still be Prime Minister by the end of the week, the answer is yes, he will. The only thing that could force him out of office immediately would be if Lord Hutton accused him outright of lying - which nobody seriously expects.

Mr Blair could even emerge a strengthened figure, if he wins the tuition fees vote by a clear margin on Tuesday. But if that vote is lost, or won by a hair's breadth, and if the Hutton report criticises the behaviour of Downing Street officials, and with no Iraqi weapons found, Mr Blair may find his authority fatally damaged.