'Dreamland Welcomes You" reads the fading sign as we pull into a large, empty car park just off Margate seafront. Above a huddle of Winnebagos and catering vans looms the skeletal frame of this abandoned amusement park's scenic railway: rusting rails leading nowhere, ticket booths firmly shuttered.

Gloomy doesn't quite do the scene justice. That special air of salt-sprayed nostalgia that infuses down-at-heel British seaside towns heightens everything here, turning the depressing into heartbreaking, the happy into bittersweet. You can understand why Bafta-winning writer-director Dominic Savage has chosen this spot for his latest contemplation of love and its associated pain and joy.

Savage grew up in Margate, in a flat overlooking the very car park where actors and crew for his set of short dramas are now gathered for lunch. His dad was a seaside organist. "It's been burning inside me for a long time and I thought that if I didn't do it now, I probably never would. A series of love stories in a place that I consider to be romantic. It felt absolutely right."

The idea is a departure for Savage, whose television films such as Freefall, Born Equal and the two-part Dive tend to take a longer, more involved, form. This time he is making five half-hour dramas for BBC1 with the catch-all title True Love, featuring some of Britain's best television actors. David Tennant and Downton's Joanne Froggatt star in the first as a happily married couple, with Vicky McClure as Tennant's long-lost love; David Morrissey, Jane Horrocks, Billie Piper and Ashley Walters are among those also appearing in dramas that stand alone but, through shared characters and setting, form one coherent tale about the impact of love on ordinary lives.

A sense of place is never far from the surface in Savage's work, and his love/hate affair with Margate is the sixth storyline here. It was Tracey Emin who persuaded him to return to their old home town to make the drama, he says, after they met at the opening of Turner Contemporary, the new arts centre that sits on the seafront. "She was incredibly emotional about the place, as was I, and she said, 'You've got to make a film here, Dominic, you've just got to.' I thought, 'Yes, this is it!' It was clear I had to do it."

On a brief tour of the town, we pass the smart house where Tennant's character lives with his wife, and the once-grand townhouse, now broken up into flats, that Lacey Turner and Walters call home.

"The other day we were shooting in a place that I used to go with a former love," Savage says. "I didn't consciously choose it because of that, it just happened to be a very dramatic location. It was only when we were shooting that I realised why we were there. So this film is full of places that I've been, and feelings that I've felt."

As darkness falls and the lights along the seafront slowly wink on, we head first to the beach, where the actors' voices are swallowed up by the wind that whips at our clothes. It is a relief to step inside the formidable grey towerblock that dominates the skyline, and head up to the flat belonging to Morrissey's character, Adrian, for a closer look at Savage's unconventional working methods.

There is no script, just a story outline, character development and improvisation around it – a way of working that reminds me more of devised theatre work than television filming. Savage, who unlike his name has a gentle manner and a generous, delighted laugh, works, reworks then reworks again a scene between Morrissey and his on-screen teenage daughter.

"It's a very different way of working," says Morrissey. "It's quite nerve-racking. For a half-hour drama there are 10 pages of script. Dominic breaks it down into scenes and will tell me, for instance, that my character is in the back of a cab talking to a friend about his internet dating and how it's going, and I'll just start talking about these things."

Savage, though, is clear he doesn't work this way for the hell of it. "I've always wanted it to be successful and to connect with the audiences; for them to feel that difference and mood – because then I can do it again and again," he says. It would, he concedes, be easier to sit at home, write a script and then present it to the actors; a far less stressful way of working that is more guaranteed to get results.

Not that Savage appears particularly stressed – rather, he seems to revel in the open-ended nature of the stories he is making. But, says Morrissey, this method doesn't always work. "Sometimes you talk over each other, sometimes you hit a brick wall, and you never know when the scene is going to stop. You don't know when it's going to end."

It's a very collaborative process, with to-and-fro between Savage and the actors. "This way of working really gives you a freedom: sometimes you feel liberated from the script, and sometimes you realise why writers get paid so much," Morrissey laughs.

It is an approach that has proved successful for Savage in the past – and one with which Morrissey is familiar, having worked with him on other projects. "I knew I had to join in – but it could be terrible; I could just wonder what the hell am I doing? The whole series is about love, and people who find love, and there were times where it seemed I could only declare my love in terrible 70s song titles."

Watching Morrissey improvise, I am immediately struck by how brilliantly Savage's process captures the way people actually speak to each other. Months later, however, seeing the first finished episodes (Morrissey's story comes later in the run), I also wonder whether that might not always be a good thing. We do tend to talk in cliches about love, repeating the same trite lines because our emotions are difficult to express. Sometimes we could all do with the help of a good writer.

Savage talks about how different actors approached the project in different ways: some spent a long time looking into their characters, while others, such as Walters, were more instinctive and immediate. For Walters, that really pays off: his portrait of a new dad, struggling with the mundane reality of work and family, feels particularly real. Some other characters in the series feel less rounded: slipping in and out of each others' lives with great dramatic effect, but not always enough background.

"I always wanted each of the films to encapsulate love in a completely truthful and visceral way," Savage says. "With love stories, the films that really work are the ones where you completely believe it – but so few do that. To make drama that has something to say about real lives and relationships, but at the same time is very personal to you and your feelings about love and relationships and their complications … hopefully that's the greatest expression."

Savage and Morrissey continue to work on their scene while, through the large windows behind them, night falls thickly over Margate seafront. In the dark, Emin's love letter to Margate – "I never stopped loving you" – is illuminated in neon. Inside, Savage is creating his own love letter to the town, and to love itself.

TV-on-sea: British coastal dramas

Dive

Dominic Savage obviously has a thing for the seaside – his heartbreakingly beautiful tale of young love was filmed in Skegness, with long, gorgeous landscape shots punctuating the film.

Blackpool

Way back in 2004, before Glee or Smash made musical television mainstream, the BBC gave us Blackpool, a musical comedy drama starring Davids Morrissey and Tennant – both of whom also appear in Savage's True Love. Morrissey, in particular, is fantastic.

Sugar Rush

Channel 4's first-rate drama series based on Julie Birchill's novel starred Lenora Crichlow and Olivia Hallinan as teenage friends enthusiastically exploring their sexuality in Brighton.

Howard's Way

With a theme tune that was possibly better than the actual show, this late 80s BBC series set in a fictional south coast English town was heavy on yachts and soapy drama.

• True Love is on BBC1 from 18 to 22 June. Fear, a new play written and directed by Dominic Savage, is at the Bush theatre, London W12 from 18 June to 14 July