Landing back home, Johnson will face angry British MPs who return to Westminster following a momentous Supreme Court ruling that the PM's decision to suspend parliament was unlawful.
British Prime Minister Boris Johnson landed home on Wednesday as determined as ever to push through Britain's departure from the EU as he faced reinvigorated calls for his resignation as well as opposition to his plans after the Supreme Court ruled he had unlawfully suspended parliament.
But none of this could be gleaned from Johnson's speech at the UN General Assembly in New York on Tuesday. His late-night appearance at the podium referenced "terrifying limbless chickens" and "pink-eyed terminators" but only mentioned Brexit once.
During the 20-minute address that drew laughs and baffled looks from delegates, Johnson struck a light tone on a serious subject as he warned of technology's capacity to control citizens.
He made no mention of Britain's highest court ruling earlier in the day that his decision to suspend parliament amid a Brexit impasse was unlawful.
The shock ruling plunged his plans to exit the EU by October 31 into crisis and sparked calls by opposition MPs that he resign immediately.
Will they, won't they?
It is unclear exactly what will happen next in the tortuous Brexit process following the court's momentous decision, although Johnson can expect a tongue-lashing when parliament sits again on Wednesday morning.
Johnson has insisted he will lead Britain out of the EU on that date with or without an exit agreement, but most members of parliament are equally determined to prevent a so-called "no-deal Brexit" scenario.
The House of Commons, where Johnson has no majority, will reconvene at 1030 GMT after the ruling voided the prorogation.
Before the suspension, parliament passed a law requiring Johnson to ask the EU to push back the deadline if no exit deal was agreed by October 19.
Opposition Labour Party leader Jeremy Corbyn said he and other opposition legislators would focus on ensuring that Johnson abided by that law.
Asked by reporters in New York on Tuesday how he planned to overcome that legal obstacle, Johnson simply ignored the question and insisted Brexit would take place on October 31 come what may.
Johnson has repeatedly said his preferred Brexit outcome would be to agree to an exit deal with the EU's 27 other members before the deadline and that he was hopeful he would achieve that.
Johnson parades his tech nightmares at UN
At the UN, Johnson painted the possibility of a future where devices in every household "monitor your nightmares, monitor your fridge," and where smart cities are "as antiseptic as a Zurich pharmacy."
"'Alexa' will pretend to take orders but this Alexa will be watching you, clapping her tongue and stamping her foot," Johnson boomed, suggesting "there may be nowhere to hide."
"As new technologies seem to race towards us from the far horizon we strain our eyes as they come, to make out whether they are for good or bad, friends or foes.
"AI, what will it mean?" he asked of artificial intelligence.
"Helpful robots washing and caring for an ageing population or pink-eyed terminators sent back from the future to cull the human race?" Johnson pondered.
He went on to wonder whether synthetic biology could restore tissues "like some fantastic hangover cure" or "bring terrifying limbless chickens to our tables."
The Conservative leader made an impassioned plea for technology to be a force for good and said he was optimistic it could "serve as a liberator and to remake the world wondrously and benignly."
He called on world leaders to agree to a set of guidelines to ensure that new technologies are designed ethically before inviting them to join him at a tech summit in London next year.
Return to Parliament
The judgement has dented Johnson’s authority, prompting calls for his resignation and casting further doubt on his promise to pull Britain out of the EU on October 31, come what may.
Corbyn said on Wednesday now was not the time for parliament to try and bring him down.
"Quite simply our first priority is to prevent a no-deal exit from the EU on the 31st of October," Corbyn said in an interview on BBC Radio 4.
The Conservative leader was due to arrive back from New York in the early hours, heading straight into a political maelstrom.
John Bercow, the Speaker of the House of Commons, said there would be no Prime Minister’s Questions — a weekly session held on Wednesdays — but there would be “full scope for urgent questions, for ministerial statements, and for applications for emergency debates.”
The prime minister is likely to also renew his call for an early election to end the standoff with parliament, having said in New York on Tuesday that it was “the obvious thing to do.”
Following his UN address, he flew back to Britain where a political storm awaits him, cutting his New York trip short.
Whether Johnson is still prime minister then remains to be seen.