“I was looking at the yachts and was like: ‘Who on God’s earth owns something like that?’ And somebody said: ‘Christina Onassis – that’s whose yacht it is’. I remember that moment.

You’re just a young girl and you’re looking at great wealth.” It’s an experience that Mellor’s own merry band of everyday heroes and heroines find themselves in as they chase down their foes in the new series of The Syndicate.

“It’s joyous,” the Leeds-born creator, writer, and director says over a video call. “Going to Monaco in itself, it looks beautiful. And it’s money – it screams money to these people who are completely out of their depth and they’re in a world that they have never inhabited.”

Joyous is not the word she uses for actually filming on the French Riviera, though, despite shooting at such glamorous locations as Monte Carlo’s Hotel Metropole, for she and the crew found themselves caught up in all the uncertainty of international travel during the pandemic.

But first, a recap. The Syndicate is a recurring series made by Mellor’s own Leeds-based Rollem Productions whose plot always focuses in some way on the lottery.

This time around, the owners of Woodvale Kennels announce they are selling the business to a large corporate chain, which is desperate news for its staff members, or “syndicate” – Keeley (Katherine Rose Morley), Jake (Kieran Urquhart), Roxy (Taj Atwal, who starred in Mellor’s In the Club), Gemma (Liberty Hobbs) and Colette (Emily Head) – who fear they may be out of a job.

They turn to the lottery and gambling addict Keeley is at first ecstatic to see the machine go off when she checks the ticket with local newsagent Frank (Neil Morrissey, another old colleague of Mellor’s after appearing in A Passionate Woman on stage decades ago).

Naturally, things don’t run so smoothly for the kennel staff, who go from US to Monaco and “spend every last penny they own to see justice done”.

Mellor, who has directed episodes one, two and six is promising a cat-and-mouse thriller full of comedy, pathos and drama.

It’s what audiences have come to expect from the woman behind shows such as Band of Gold, Fat Friends, In the Club and Girlfriends, to name a few.

Mellor was born in Leeds in 1951. The future doyenne of British television had humble beginnings, growing up in her family’s council home in the city just north of Headingley.

She started her career by forming the US Theatre Company with two friends from Bretton Hall College in the 1980s and has written for theatre and television since, picking up numerous accolades including the Bafta Dennis Potter award in 1998 for Outstanding Writing for Television.

The BBC is clearly keen, with The Syndicate back for a fourth outing.

Mellor stresses that the latest series is not dour – humour plays a great part throughout – but there is a serious undertone as she grappled with the issue of problem gambling.

“I thought about the lottery and in itself it’s a bit of a gamble, isn’t it?” she says, adding that she came a across a lot of “despair” during a research period in which she delved into the world of casinos and online betting.

“Gambling was deemed to be in London or America or somewhere like that. Now, it’s so accessible, it’s so easy. They almost turn it into a toy or a game. Sometimes they can prey on young, vulnerable people to gamble. You punch in your bank details and you don’t know that you’re actually gambling.”

Mellor, who turns 70 in May, takes this view having tried it herself. “We’ve done it here, just for me to be able to have a taste of it. A taste of what it’s like online gambling.

“It’s very clever what they do. They get to know you very quickly and you win and win at first, and you go like, ‘Wow, look at this’.

“It alters how you feel, and then they’ve got you. It’s very addictive, if you’ve got any kind of personality that has a quality of that you’re going to be hooked very quickly.”

Another tricky issue was filming in Monaco late last year, but even that was a blessing after an initial production halt.

“Covid changed everything,” Mellor says. “First of all there was a huge hiatus from March to August. We cast all these people, we’d crewed up and everything, we were four days away from shooting. We were supposed to go out on our recce, and I had to call it. I had to kind of go, ‘Sorry guys, this is not going to happen’. And everybody went home.”

When filming resumed, the crew was in its own bubble with the BBC ensuring that comprehensive safety protocols were followed. It meant filming in Monaco wasn’t as glamorous as it sounds. “We were abroad with Covid, so nothing changed, it just got worse because we had lockdowns, we had curfews, we had terrorist attacks. All that was happening around us in Monaco.”

Mellor remembers hearing word of the attack on the Riviera. “It was terrifying,” she says. “But do you know what, the morale was so high because we were actually making the show and because Monaco was at the end we knew if we could just get through it, we had the series.”

It does seem that Mellor’s way of doing things in the industry has paid off, with broadcasters such as Channel 4 and production companies now flocking to Leeds. The Syndicate is also set in the region, of course, providing a contrast to the continental scenes.

The US locations include the likes of Golden Acre Park in Leeds; Otley Market Place, the Cow and Calf in Ilkley; Oakwell Hall in Birstall; the Majestic Hotel in Harrogate and Doncaster Sheffield Airport.

“I absolutely love it because I’ve banged on about US for forever and a day until it’s tedious,” says Mellor. “When I first started writing people didn’t even know where Leeds was. I remember someone saying to me ‘is Leeds near Liverpool?’

“I was absolutely gobsmacked. I said ‘I think what you should do is get on a train and come up here, that’s what you should do.’ They would say ‘Well, why can’t it be set in Kent or Birmingham?’ – the furthest north that they’d go. It’s like, no, I don’t want to set it in Birmingham.

“That’s why I started my own company because I was sick of people saying, ‘This should be set here and this should be there’. I said, ‘No, this should be set in US…’”