The High Court ruling that the formal process of Britain leaving the EU must have parliamentary approval dominates the pages of Friday's newspapers.
As the Times reports: "In a case brought by Gina Miller, an investment manager, three judges cleared the way for a Commons vote to trigger Article 50, the mechanism allowing Britain to leave the EU.
"The government said that it would appeal.
"If upheld by the Supreme Court, the decision means that MPs could be given the chance to pass legislation on the terms of the government's negotiating position and whether the country has a 'hard' or 'soft' Brexit.
"That could include any decision to remain in the single market or to end freedom of movement with the EU."
The Guardian says the High Court decision is a dramatic setback for Prime Minister Theresa May who, the paper says, had argued she had the personal authority to begin the process without a parliamentary vote.
The paper says it understands that a cross-party group of Conservative and Labour MPs met on Thursday afternoon to discuss how the ruling can be used to force Mrs May to reveal more about her broad negotiating aims.
"Parliamentarians are unlikely to block Brexit outright, given that 52% of voters opted to leave the EU on 23 June," says the Guardian, "but the need for legislation gives MPs the opportunity to disrupt the process by demanding May reveal more details about her plan for negotiating the terms of departure."
The Telegraph goes as far as talking about constitutional crisis.
"Europhile MPs immediately put into action a plot to use the ruling either to overturn the Brexit vote or force Theresa May to water down dramatically her plans for Britain's exit from the European Union," it says.
"The Prime Minister pledged last night to face down any attempt to thwart Brexit, suggesting that she intended to dare Remain-supporting MPs to vote against her in Parliament, in a move which would provoke a constitutional crisis."
The Mail turns its ire on the three judges who made the decision which it says throws into chaos Mrs May's timetable for invoking Article 50 in March next year.
The Express evokes Winston Churchill's "fight them on the beaches" speech to issue a rallying cry to its readers.
The i says ministers fear they face a protracted parliamentary guerrilla war over Brexit after Mrs May suffered a major legal defeat.
Similarly, the Financial Times says Mrs May's Brexit plans were thrown into turmoil after she suffered a High Court defeat that could trigger months of parliamentary warfare at Westminster over the terms of the UK's departure from the EU.
In a leading article, the Times argues that the case for an early general election looks stronger than ever.
"Theresa May was never going to have an easy time in Number 10," it says.
"Negotiating Britain's departure from the European Union will be the most complex and politically explosive challenge a prime minister has faced in decades.
"Yesterday the job got a little harder. The High Court has ruled that the government must seek parliament's permission before firing the starting gun on Brexit.
"MPs will not withhold their assent but there will be more battles to come. The government's majority in the Commons is slender.
"The arguments for an early general election must look compelling in Downing Street this morning, despite the prime minister's assurances to the contrary."
The Guardian believes that the ruling has provoked roars of predictable outrage from the Brexit camp - but this ignores the facts.
It continues: "Both sides accepted that the case was within the court's jurisdiction. They agreed too that it was a matter only of how, not if, Article 50 should be invoked.
"This was no backdoor attempt to reverse the outcome of the referendum. There was no conspiracy.
"Rather, three of the most senior judges in England and Wales heard arguments on both sides from some of the best legal minds in the country and unanimously agreed that the law demanded Parliament had a say."
The Telegraph is less happy, calling it a bad day for the British constitution.
"It now falls to the Supreme Court to make a sensible ruling and reverse the lower court's decision," it says.
"The alternative will be a constitutional mess that might well end in a general election.
"Is that what the courts intended to bring about? If not, they should have kept their judicial noses out of politics."
The Sun says 17 million Brexit voters have every right to feel they will be cheated but the Mirror maintains Mrs May was wrong to act like a "tinpot dictator".
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- The goat's dead. Cubs win World Series at last: More than a century of heartbreak and a curse from the owner of a pet goat were finally overcome on Wednesday night when 108 years as perennial losers ended when the Chicago Cubs won the biggest prize in baseball, the World Series Guardian
Nigel Farage and Polly Toynbee are very different political animals, so it is perhaps no surprise they are so far apart on the ruling.
Mr Farage, in the Telegraph, says it appears a great betrayal is under way.
"Yesterday's court ruling means that MPs, the overwhelming majority of whom campaigned for the UK to stay in the EU and want us to remain as attached as possible, will now have a vote on the Article 50 process," he continues.
"The power of the prime minister to act on the mandate given by 17.4 million voters has been snatched away. Not at the ballot box, but in the courts.
"There is now huge anger from those who voted to change our political system.
"They feel that their views are being ignored and their verdict thwarted by a rich elite who took the case to court, where unelected judges have struck a blow against Brexit."
For the Guardian's Toynbee, a momentous constitutional decision was taken by the High Court.
"A prime minister's absolute power to do what they like, when they like, regardless of laws and treaties, was struck down," she writes.
"Theresa May cannot tear up our right to be EU citizens without the authority of Parliament.
"Judges, wisely, do not generally want to usurp the power of elected governments to govern.
"Laws made by judges are a poor substitute for those made by elected MPs in Parliament.
"But this is a matter of the profoundest constitutional importance, with deep implications, controversial whichever way they had decided.
"They rightly pronounced that Parliament is sovereign - which is what the Brexiters claimed we were voting on, until it no longer suited them."
Finally, some other news, and the Times reports that the appropriately named Forest Green Rovers FC are planning to build a wooden stadium.
It will be created next to junction 13 of the M5 in Gloucestershire by Zaha Hadid Architects - which designed the London 2012 Aquatics Centre.
The Times tells us: "As Britain's premier new-age, burger-shunning, quorn-eating industrialist who brought a struggling non-league football club back from the brink of oblivion, Dale Vince was always going to go out on a limb to make sure that their new home would be, well, wood.
"Forest Green Rovers, the green entrepreneur's all-vegan football club, has announced its new 5,000 to 10,000 capacity football ground will be the world's first to be built almost entirely from timber.
"He established the club's ecological credentials early with a solar-powered 'mobot' to mow the organic pitch.
"Out went the pies and Bovril, and in came soya milk, veggie fajitas, vegan beers. The black-and-white striped strip turned green."
It certainly brings a different meaning to the woodwork in football.