Boris Johnson is on Monday expected to try and fail again in his bid for a snap election to resolve the Brexit crisis.
Opposition parties are still against going to the polls, as they do not trust the prime minister to abide by a law they have passed to block a no-deal Brexit on October 31.
Johnson is also due to suspend parliament this week until mid-October, with Monday the last day for which any business is scheduled.
And he travels to Ireland on Monday for talks with Taoiseach Leo Varadkar, which could be crucial for his efforts to renegotiate the Brexit deal and in particular the Irish backstop.
It is difficult to remember a more unpredictable time in politics, here’s how things could play out.
Johnson’s reaction to being denied an election
The PM is widely expected to be defeated again in a vote on whether to have a snap general election in mid-October, and his reaction to that could prove key this week.
He is currently scheduled to prorogue parliament on Tuesday, but could delay it until the end of the week if he wants to make a fresh attempt at calling an election.
If he does, he will have to convince Labour or other opposition parties that no-deal Brexit is off the table on October 31, and that the date of any election cannot be moved to after the withdrawal deadline by the government.
So instead of offering a vote under the Fixed Term Parliaments Act, which requires a two-thirds majority, he may seek to bring forward legislation which locks in the date and only needs a simple majority of MPs.
As one Labour source says, that is fraught with danger as MPs will be able to hang on it all kinds of amendments.
Plus opposition parties will have even less trust in the PM after Dominic Raab on Sunday suggested the government could try and bypass the anti-no deal legislation which passed through parliament last week by finding a legal loophole in it.
But HuffPost UK understands that Labour is still not ruling out backing an election this week, if some kind of mechanism can be found to bind Johnson’s hands on no deal.
If it cannot, Johnson may choose to go ahead with prorogation, catch breath, and come back to fight another day.
If he does choose to suspend parliament, the Hilary Benn anti-no deal bill should get royal assent and become law, but again opposition MPs will be watching the government like hawks to ensure the convention is upheld.
Brexit deal negotiations
For now, the only thing Johnson can really do if he cannot get an election is strain every sinew to try and get a Brexit deal at the October 17-18 European Council summit.
Irish leader Varadkar has been playing down the significance of Johnson’s visit on Monday, but it is still a significant moment.
Johnson has made clear that ditching the Irish backstop, to maintain an invisible border between Northern Ireland and the Republic, is his number one priority.
Varadkar has said he does not expect a “big breakthrough” but stressed that the talks would “be an opportunity to get to know each other a little bit better, to see if there is common ground”.
Shadow Brexit secretary Sir Keir Starmer said Labour would be watching to ensure the government does not “backtrack” on commitments to protect peace and avoid a hard border.
“When Boris Johnson meets the Irish prime minister, he must make absolutely clear there will be no rowing back and the Government will not take the negotiations down such a reckless path,” he said.
Tory resignation watch
Amber Rudd’s dramatic weekend resignation from the cabinet and Tory whip has set hares running in Westminster and there is every chance that more could follow her out of the door in protest at Johnson’s scorched earth Brexit strategy.
As well as the sacking of 21 Tory Brexit rebels, one of Rudd’s key complaints was that the government did not appear to be serious enough about getting a Brexit deal.
A string of cabinet ministers thought to be at risk of resigning, including Nicky Morgan, Julian Smith and Matt Hancock, signalled on Sunday that they were staying put for now.
But Justice Secretary Robert Buckland gave an indication of just how febrile the atmosphere is with a tweet in which he suggested he had to get reassurances from Johnson that he would not break the law to force through Brexit.
Ministers may also look for more evidence that Johnson really is trying to get a deal, which highlights the importance of the Ireland meeting.