Catastrophe's Rob Delaney: "It would be bad parenting to move my children back to America"

“We were ruined,” he says. “But we learnt from it, thank goodness, and we did take a little break between two and three. We love making the show but don’t want to kill ourselves. We just want to harm ourselves.”

The hours are still long, but putting the show together is not as practically difficult as it used to be. The first series, which aired in 2015, was largely written when Delaney and Horgan lived on different continents. They now have the luxury of being in the same city – Delaney has since moved with his family from LA to London, although he hadn’t necessarily planned on such a big change.

“I thought I was moving here for a few months,” he says. “I thought we’d make one series and Channel 4 would say, ‘Well, we’ve made a colossal error, and now you can go home.’ But that isn’t what happened , shockingly. So my life here has blossomed. We’ve been here two and a half years now. My eldest two go to school here, our third child was born here. Yeah, we live here – big time.

“I’m crazy about London, I love it so much. I love the NHS. I love the BBC. I love the Tube. I love the bus. I love tea. I love bacon sandwiches, I really do. And I vastly prefer writing in the same room as Sharon.”

Is their partnership divided into specialisms? Who does what?

“Ideally, it’s Sharon at the laptop and me yelling things, and then we read it out aloud together,” he says. “Now we’re more attuned to each other. I might have said with series one that I was more prone to put in a ‘hard’ joke, and Sharon would be more of a story architect, but now the lines are blurred.”

From the beginning the two stars drew on their own marriages for material: both have young children; Delaney’s three boys are all under six. Catastrophe has always been scabrously funny, but as the marriage of their characters (also called Sharon and Rob) progresses, the sense of jeopardy deepens. If you’re rooting for Sharon and Rob, it’s because you’re genuinely afraid for them.

“Marriages end, so there is jeopardy,” Delaney says. “Even in a good life that you’re enjoying there’s jeopardy because you have strong attachments and a very serious interest in preserving the status quo.”

In Catastrophe the distinct possibility that love does not conquer all is always lurking. “That’s what we try to do with the show, to use all the colours in the palette. It seems to us that that’s a more responsible way to look at marriage, comedy and life.”

Delaney is also conscious that life is happening at home, that while he spends an 80-hour week pretending to be a harried parent, his wife is somewhere actually being a harried parent. And he is missing out. “It’s acutely painful when you know that they need you,” he says, “and you know that the measure of good parenting when they’re little is just how often you’re there. Is your arm around them? Are they sitting on your chest while you’re trying to read a book? Then you’re being a good parent.”

He turned down “something massive” just recently. “I had to wrestle with it a little bit, but I said no. It was the right decision, and now that I’ve lived through the time when I would have been working on it, and I got to spend it all with my little kids, I’m so glad that I didn’t do that AMAZING thing that definitely MILLIONS of people will watch.”

Delaney is a man as fulsome in his praise as he is vitriolic in his hatreds. The third series of Catastrophe contains the last performance Carrie Fisher ever gave, as Rob’s hilariously difficult mother Mia. “The stuff she does in this series is quite poignant,” says Delaney. “Thank God we were cognisant of the privilege of having her with us, so we always made sure we put our best foot forward whenever we wrote for her. ”

His bile, presently is reserved for Donald Trump and anyone who has anything to do with him. “I’m in the post-election phase,” he says, “where even if you have peripheral associations with Trump, I want you to suffer.”

Delaney is a prolific tweeter – he was once named the funniest person on Twitter by Comedy Central – and he’s been in attack mode when it comes to Trump for a number of years. “I thought I was just joking around with a clown, like so many others did,” he says now. “I’m not self-flagellating and saying mea culpa, because he is a clown, he continues to be a clown. He’s just a dangerous one. But to think that he couldn’t win? Yeah, shame on me.”

In hindsight, he sees that the “stage was set” for a Trump victory when more people didn’t vote than voted for either candidate. “That speaks to a cancer-ridden electorate,” he says. “The cancer of wilful ignorance, of laziness. When the largest number of people vote for no one, you can end up with somebody like Trump. It’s my fervent prayer that his election is a wakeup call. I mean, it has been for me. I thought I was awake.”

A part of him wishes he was where the action is. “I’d like to be in the United States right now, with Trump as president. I’d like to be physically present at protests.” But he feels an impending healthcare crisis, following Trump’s pledge to dismantle the Affordable Care Act, has left him stranded, at least temporarily. “In the United States of America you could be denied healthcare if you have a pre-existing condition, which can literally include ‘has had a child’. It would be bad parenting for me to bring children back to that country.”

Delaney has toured the UK with his stand-up act, and he means to do so again, but not right away. In the meantime there’s a fourth series of Catastrophe to prepare – although the further adventures of Sharon and Rob have yet to be written. Does he have any idea what will happen?

“I will say this – and Sharon and I haven’t agreed this and I reserve the right to change my mind – it might be fun to jump them down the road a bit.” In order to keep the drama going, they may have to hit fast-forward, as they did between series one and two. “And also I’m getting fatter at a rate I think people might not believe,” he says. “We might actually need time to pass.”

Catastrophe is on Channel 4 tonight at 10pm