‘The glass ceiling for dogs had been broken!’ Herbie the cockapoo on his years working for Sunak and Starmer

Much to my surprise, I got a FaceTime call from David Cameron. I hadn’t heard a word from him since I had failed to turn up to the launch of his desperately dull political memoirs some years back. I just couldn’t face all the self-serving lies and self-congratulatory speeches. Mind you, I could have done with the advance. Dave got the best part of £800k. A lot, lot more than I am getting for my own autobiography. And my book is far more accurate.

“Hi, Big Dave,” I said.

“It’s now Lord Dave,” he replied. He couldn’t keep the smirk off his face. A face that was weirdly unchanged despite the intervening six years. The Picture of Dorian Gray. Somewhere in his attic, there must be a portrait ageing by the hour. It was remarkable. Most former prime ministers look ravaged by the strain of office. But Dave is completely unaffected. No one ever found it easier to forgive himself for his mistakes than Dave.

“Hi, Lord Big Dave,” I corrected myself. “What’s with the peerage?”

“Isn’t it great? Rishi has looked around all his Tory MPs and concluded none of them are any good. So he’s asked me to be his foreign secretary.”

“That’s mad. But you don’t know anything about foreign policy. Last I heard, you were responsible for Brexit. Not exactly a triumph of international diplomacy. And then you destabilised Libya by bombing it.”

“Details, Herbie. Details. These days, all a foreign secretary has to do is jet around the world first-class while trying not to start a war. It’s a piece of piss. If James Cleverly could manage it, then anyone can.”

It was hard to fault his logic.

“So, I’m asking you if you fancy becoming my adviser in the Foreign Office,” he continued. “You always were about the only vaguely competent member of my No 10 Brexit team. And it won’t be for very long. The Tories will be out of government soon enough. What do you say?”

“Er, thanks but no thanks. I’ve got my reputation to think of. But very kind of you to offer.”

“I thought you might say that. Never mind. Hope to see you again before too long.”

It always was easy come, easy go with Cameron.

Still, it was reassuring to know I was missed and that I was still in demand. The glass ceiling for dogs had been well and truly broken. But there was one invitation I couldn’t refuse. This one came through the post. A request – make that a summons – to give evidence before the Covid inquiry. As one of those who had been working inside No 10 at the time, my presence was required.

The makeshift courtroom in Paddington was packed well before the start. It was as if no one had seen a dog on the witness stand before. Enough to make me feel nervous. Normally, I take these sorts of occasions in my stride. Dame Heather Hallett took her chair and we were off.

“I swear by almighty dog that the evidence I shall give is the truth, the whole truth and nothing but the truth.”

It was Hugo Keith asking the questions. Had all my WhatsApp messages been deleted like everyone else’s? Er … no. As far as I was aware, they were all still on my phone. Why wouldn’t they be? Now it was Hugo’s turn to look confused. Because everyone else had said some of their messages had mysteriously self-destructed. Clearly, no one had thought to remove any incriminating messages from the dog’s phone.

We moved on. How was my memory of events in Downing Street during the pandemic? About as good as could be expected given the chaos. Trying to get Boris to concentrate on the data while stepping over one or two staffers who had been partying a bit too hard the night before. Trying to make myself heard above the karaoke machine while Michael Gove was asking Michelle Mone what had happened to the PPE she had promised to provide. There were a few gasps from the public gallery.

“I see,” said Hugo. “That’s all the questions I have for now. I suggest this is a good time to adjourn for a break.”

And that was that. My truth. Which didn’t appear to be totally the same as everyone else’s truth. Still, this wasn’t my problem. The inquiry could make of it what they liked. They could ignore it or recall some of the earlier witnesses who had spent hours trying to apportion blame away from themselves. But this wasn’t my fight. I could look myself in the mirror and feel good about myself. Boris, Dom and the rest could sweat it out. Not that there would be a real reckoning. People like them are rarely personally held to account.

We’re getting to the end now. The death rattle of the Tory party was loud enough for even its devotees to hear. It was no longer a matter of if the Conservatives fell apart, but when. The infighting became even fiercer and there were at least five factions on the right all falling out with one another. The centre of the party had long since given up. They were mute.

Meanwhile, Rishi got tetchier and tetchier as things collapsed around him. He couldn’t understand why the country wasn’t more grateful for all he had done for it. He even made the schoolboy error of getting his wife to introduce him at his final party conference. Nothing shouts “I don’t have a personality of my own” more than that.

Rishi joined his wife on stage to awkward applause once she had finished her five-minute speech. “Marrying you is the best decision I ever made,” he declared. At which point I thought: if I had married the daughter of a billionaire, it would probably be one of the best decisions I ever made also. Certainly in the top three.

The death knell came with the rattle of my phone. It was Larry.

“Long time no speak,” I said. “Good to hear from you. What’s up?”

“How are you, Herbie?” he replied. He sounded breathless.

“I’m good.”

“Excellent. Now, the reason I’m calling you is because Rishi is going to call an election tomorrow for 4 July.”

“How do you know?”

“I overheard Craig Williams saying he was about to put a bet on.”

“Who is Craig Williams?”

Related: It’s all so unfair. And Rishi has no one to blame but himself | John Crace

“Rishi’s parliamentary private secretary. He’s with the prime minister the whole time. If anyone knows, it’s him.”

“But why is he doing it now? It’s madness.”

“He thinks that if he succeeds in wrong-footing his own party then he must also be wrong-footing the opposition.”

“That’s great. Thank you.”

“Don’t just thank me. Put a bet on yourself. I have. I’ve put on a grand at 5-1. Once it’s paid out, I’m off on safari to the Serengeti. I’ve always wanted to see some lions.”

“But that’s illegal. Insider knowledge.”

“Sure, it is. But there have to be some perks of living here. You can’t even go out for a piss without the photographers snapping away. And who is ever going to suspect a cat?”

“You’re right. You’ll be fine. But I’m still not going to do it.”

“Suit yourself. By the way, that invitation to an election-night party is still open.”

“You’re on.”

I may not have been up for a bet, but I was up for passing on the news. I called Keir. The election was going to be called the next day, I said. So, start writing your speech. Book the battlebuses. Reserve the prime advertising sites. Get your social-media team activated. This is your moment to get ahead of the game.

“Are you sure about this?” Keir asked.

“Absolutely. My source is impeccable.”

“I won’t forget this. I promise.”

“There’s also one other thing I might be able to help you with …”

“What’s that?”

“The Euros. I’m friends with one of Gareth Southgate’s dogs. He’s a cockapoo, like me. He’s offered to get Gareth to make the England team play really badly in the qualifiers and the first knockout game. That way, the Tories don’t get any feelgood bounce from the football before the election. Then, once it’s over and you’re in No 10, everything changes. He can guarantee a penalty shootout victory and a last-minute winner. A place in the final is nailed on.”

“Do that and I will love you for ever, Herbie,” said Keir. He sounded almost tearful.

“Count on it.”

You know the rest. Well, not quite all. I did have a small part to play in Rishi missing the D-day commemorations. Lord Big Dave did text me to say he was a bit worried that the prime minister was going home early and that it would look bad. I texted back to say that no one would mind in the slightest. Everyone was totally fed up with the 100-year-old second world war veterans as it was. Always going on about the sacrifices they had made. It was time to let bygones be bygones. We were fed up with the war and being grateful.

“You’re right,” said Lord Big Dave. “I’ll tell Rishi it’s fine for him to leave them on the beaches and come home to do an interview with ITV.”

Cameron really is the most gullible man I’ve ever met. So sweet. Needless to say, my next call was to Keir. “Rishi’s not going to be in Normandy for the international celebrations. So, make sure you are. And book your photo opportunities with Joe Biden, Emmanuel Macron, Olaf Scholz and Volodymyr Zelenskyy. Make sure that you’re the one who looks like the prime minister.”

“Gotcha,” said Keir. “I owe you again.”

That wasn’t the end of it. Three weeks into the campaign, I couldn’t resist getting in touch with Buddy. The schnauzer whose house Pippa Crerar lives in. “I’ve got another story for you,” I said. I told him all about the insider betting on the date of the election.

“That’s fantastic,” he smiled. “Great narrative. Corruption in an out-of-control Downing Street. The Tories only in it for themselves. Pippa will have a field day with this.”

And she did. Poor old Rishi must have wondered why he could never seem to catch a break. But it was his election and his campaign. There wasn’t a huge amount of affection for Labour, but the country was agreed on one thing: they had had enough of the Tories.

Even so, I couldn’t help feeling nervous as I made my way into an eerily empty Downing Street on the evening of 4 July to watch the results with Larry. What if all the polls that had consistently given Labour a 20-point lead for the last six months were wrong? What if all those undecideds had chosen to give the Tories another chance? Because, well, the Tories are the natural party of government and people didn’t really trust Starmer? What if my life was just one sick joke and I was doomed never to see a Labour government?

Larry and I held each other’s paws as the clock moved round to 10pm. Then the exit poll. Boom! Labour on course for a landslide victory. On a par with 1997.

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“Tony Blair’s not going to like this,” I said.

“Who’s Tony Blair?” asked Larry.

There are some surprising gaps in Larry’s knowledge. He thinks the world didn’t exist before he was born. He’s an expert on the five – shortly to be six – prime ministers he’s known personally. But hopeless on the ones before that. I guess that’s the difference between a dog and a cat.

“Tony Blair,” I said. “The last Labour prime minister to get elected before Keir. He thinks only he is entitled to a landslide win. He’s got a bit of a messiah complex. Doesn’t like any competition.”

“Oh.”

We stayed up through the night. Partly to see the exit poll, which we still couldn’t quite trust, come true. Mainly to watch various former Tory ministers fail to get re-elected. There were cheers when Thérèse Coffey and Grant Shapps lost their seats. And Larry went wild when Liz Truss bit the dust. He had never liked her. Felt she was rude and disrespected him. However, we were both quite pleased when Jeremy Hunt held on. I mean, obviously he was a useless chancellor, but he was unfailingly polite.

Come early the next morning, Downing Street was beginning to fill up with the world’s media, there to witness the change of government.

“You can stay to watch Rishi’s farewell and Keir’s arrival, if you like,” said Larry. “It’s history.”

But I was tired. Not used to this level of sleep deprivation. Besides, I would see and hear it all much better on the TV.

“I’m going to make a move,” I said. “And you’re going to have to get used to a new cat.”

“What?”

“The Starmers have a cat. Jojo.”

Larry didn’t seem best pleased. Dogs he could tolerate. Not cats.

“Well, she’d better do as she’s told. I’m the boss round here.”

“I’m sure she will be well behaved,” I said, trying to be reassuring. “Even Keir knows you’re the one really running the country.”

“Good.”

• Extracted from Taking the Lead: A Dog at Number 10 (Constable, £18.99). To support the Guardian and the Observer, order your copy at guardianbookshop.com. Delivery charges may apply