"Donald Trump directed him to commit a crime by making payments to two women for the principle purpose of influencing an election." With those words spoken by the lawyer for Michael Cohen – the US president's longtime henchman – began the most dramatic legal and political crisis of the Trump presidency.
Put simply, a key member of Mr Trump's cohort accused him, under oath, of ordering him to commit a crime.
It shows how far the relationship has deteriorated between the embattled Mr Trump and the lawyer who once claimed he would “take a bullet” for his boss but now appears to be conspiring against him with prosecutors.
But that wasn't all. Just 240 miles away, in a Virginia courtroom, Mr Trump's former campaign chairman Paul Manafort was convicted of bank fraud and tax evasion. Although they do not relate specifically to Mr Trump or his campaign, the charges are significant in that they were brought by Robert Mueller, the rigorous special counsel investigating Russian interference in the 2016 US election.
After spending months denying any wrongdoing and extolling his staff, Mr Trump's administration looks irrevocably tarnished.
This is a watershed moment for a presidency some expected to unravel soon after he was inaugurated. It implicates Mr Trump as a co-conspirator in a crime and although constitutional scholars are divided over whether a sitting president can be indicted, it is now possible – should Mr Trump leave office before 2021 – that he could face criminal charges. And if the opposition Democrats win control of the House of Representatives in November's midterm elections, it is reasonable to expect them to initiate impeachment proceedings against him.
On the Russia front, the pressure is mounting. Mr Mueller has already charged more than a dozen Russian individuals and companies for an orchestrated social media campaign to get Mr Trump elected as well as 12 Russian military officials for hacking into Hillary Clinton's emails.
And on Monday, Mr Trump admitted that he did not want to sit down with investigators for fear of perjuring himself. His most ardent supports might stick by him. But it is worth remembering that Watergate – to which this investigation is frequently compared – took two years to oust a president. Mr Mueller’s investigation is little more than a year old.
This crisis will be felt beyond the borders of the US. Mr Trump, for all his woes, still controls the most powerful military the world has ever seen.
From countering Iran's regional adventurism to working towards a Middle East peace plan, the actions of a US president matter. A cloud hanging over the presidency threatens to overshadow global geopolitics.
Whatever the outcome, it is crucial Mr Mueller’s investigation is concluded fairly and expeditiously to return some semblance of normality to the White House.