For mild-mannered former prime minister Boris Johnson, the photographs were baffling. They showed him, hair unkempt, crumpled suit, standing in the middle of a party, raising a glass. The Privileges Committee said the photo had been taken in lockdown, but that was impossible. Mr Johnson – he always insisted people address him that way, to reflect the seriousness of his role – had been scrupulous in following Covid restrictions. To do anything else, when he was the public face of them, addressing the public on the subject night after night, would have been offensive to his upright, puritan soul.

“Are you sure this was taken during lockdown?” he asked an aide.

“Quite certain. And the committee says it proves you lied to Parliament.”

“Me! Tell a lie? But…” The very thought made Johnson’s heart skip a beat. All his life he had worked to build a reputation for scrupulous honesty. In his previous career as a journalist his copy had been so reliable that colleagues and rivals had told each other: “If Boris says it, you don’t need to check it.”

And yet, as he leafed through the committee’s report, it was clear that something terrible had happened. Here were his statements to Parliament denying wrongdoing, and here were pictures of him clearly in the middle of events that shouldn’t have taken place.

“Carrie, darling, I must resign from Parliament.”

“Really Boris, but what will your constituents do, without your constant interventions on their behalf?”

“We won’t be deserting Uxbridge! We’ll still be helping at the food bank and doing the catch-up tutoring! But this is a matter of honour. I don’t know how, but I must clear my name.”

“I have to, Dom! If I can just go back to 2020, I can find out what happened. I can fix history!”

He rose from the breakfast table and went out into the hall. Pulling a key from his pocket, he unlocked the cellar door and made his way down the rickety wooden stairs. Though it had pained every fibre of his being to do it, he had just lied to his wife. He did have a plan.

The basement was taken up with a huge object covered by dustsheets. A faint electrical hum came from underneath. He pulled the covers away and gazed at the device. This was the greatest secret of his time in office.

It was a project known only to a few. A few weeks after he became prime minister, the Conservative Party’s finest minds – Dorries, Rees-Mogg, Clarke-Smith, Nici – had approached him to with astounding news. Their after-hours theoretical physics group had cracked time travel.

“Boss! What are you doing?” Standing at the top of the stairs was Dom Cummings, Johnson’s most loyal aide, who had stayed with him when all others had fled. “We said we would never use it!”

“I have to, Dom! If I can just go back to 2020, I can find out what happened. I can fix history!”

Cummings stared at him. “You’re right. Losing you as prime minister has put Britain’s whole future into terrible jeopardy. It’s worth risking the destruction of the universe to get you back in Number 10. Fire it up.”

Gaaaaaashooomveroooosh!

The room seemed to be spinning as Johnson stumbled from the machine, his usually smooth shirt now rumpled and untucked, his hair amok. “Cripes,” he said. He felt woozy. Had it worked? He looked around him. His surroundings looked familiar. Yes! This was the Downing street potting shed. He peeked through the door. It was dark, and cold. In the distance, he thought he could hear people singing Abba. This must be it! The night of the apparently notorious leaving party, which he had been unaware of as he’d been stuck in the lab working on his Covid vaccine.

He crept out. He had to stop them. But time travel had left him disoriented. Suddenly woozy, he lost his balance and crashed through the doors into the room where the press office were mid-conga. His throat was dry. He needed liquid, and grabbed the nearest glass.

“Boss! You came!”

He turned. Everyone was looking at him. “Ah, yes, erm…” he swayed, and reached out his hand for balance. What was that sound? A camera shutter?

NEXT WEEK: Will our hero be able to correct the new problems he’s created? Will trusty sidekick Dom be able to fix things by travelling back to use the secret hadron collider in Barnard Castle? And does any of this explain where all the children came from?