The body of a man, most likely an immigrant attempting to reach England by boat, is washed up on Bognor Regis beach. Depressed by his life, poorly paid coach driver and single father Pete Green ignores the corpse and walks away. But Pete is haunted by this random act of apathy and compensates by taking into his home a teenage asylum seeker he discovers stowed away on his coach after driving a party to France.

Tim Crouch, playwright and co-writer of Don’t Forget the Driver, describes Pete as “a small man, who wants to keep himself to himself, but is forced to become engaged with the world.” Pete is literally as well as politically a Little Englander, played by the show’s other writer, the five feet, five inch Toby Jones.

Featuring a man who reluctantly becomes a good Samaritan – after a trip on which his passengers have booed as they enter Europe – Don’t Forget the Driver will inevitably be seen in the context of Brexit. Pete, having a mixed-race daughter and racist emigrant brother in Australia, reflects a number of personal and national identity crises. The show was deliberately scheduled by the BBC to screen just after the UK’s original EU departure date of 29 March, and will now coincide with wherever we are in the process by 9 April.

Crouch points out that he started work on the idea “four years ago, when we didn’t have the B-word.” But Brexit, when it came along, “certainly gave a new context to the whole thing,” acknowledges Jones.

The co-writers, though, decided that the words “Brexit” and “migrant” should never be spoken in the show. “Whenever we got too close to using one of those words, we would pull back and keep away,” says Crouch. “It felt too on-the-nose.”

Facebook Twitter Pinterest What does unspoken ... stowaway asylum seeker Rita (Luwam Teklizgi) with Pete Green (Toby Jones). Photograph: BBC/Sister Pictures

Yet Jones admits that there is absolutely no doubt about the show’s unspoken subject. “Even if you put no reference at all to Brexit in something set in contemporary Britain now, that itself would be taking a position on Brexit. But the fact that we were setting our first episode on the English coast meant everything became freighted with Brexit, even though we never spelled it.”

Don’t Forget the Driver is the first time Jones has written for a show as well as starring in it, expanding a screen acting career that includes metal-detecting comedy Detectorists and M Night Shyamalan’s twisty thriller Wayward Pines on TV, and leading roles in the movies Infamous, where he stars as Truman Capote, and unsettling ‘sonic horror’ Berberian Sound Studio. Crouch and Jones met when the latter appeared in the former’s play An Oak Tree, and Don’t Forget the Driver came to pass when Crouch asked if Jones was interested in working together on “something about coach drivers and Bognor Regis.”

The West Sussex resort has long been an English punchline, due to the similarity of its name to a rugged expletive. (“Bugger Bognor!”, King George V supposedly exclaimed when the coastal town was recommended to him.) For Crouch, though, Bognor is not a joke but home; he lived there until he was 18, and frequently returns to visit family.

There’s a history of locations being angered by their depiction on film, but Crouch has no fear of Bognor telling him to bugger off. “Anyone who had any doubts was given a copy of the scripts,” says Crouch, “which seemed to allay their fears. And Bognor looks stunning in the series … even more stunning than it does in real life. We were blessed, during filming, by a glorious halcyon spell of weather. Bognor looks transcendent. It’s important to me that this wasn’t a piss-take at any level.”

Jones was less interested in the place than the protagonist. Coach drivers, he realised, were “people one had really not even noticed in decades of being driven by them.” In an impressive example of method acting, he took Coach Driver Certificate of Professional Competence (CPC) lessons and failed his test twice, once for driving too fast and once for going too slowly – but he did acquire enough skill (just about) for the onscreen driving scenes.

“The paradox is that drivers have no authority over the passengers, but have to take responsibility for strangers’ lives,” says Jones. “You can’t be drunk, or tired, and have to be punctual. So there’s a tremendous sense of duty because your job and people’s lives depend on it.”

The pair went on a number of coach trips for research, including an outing to a donkey sanctuary, and a two-stop excursion taking in a Commonwealth war cemetery in France and Adinkerke, a town on the French-Belgian border that is almost wholly devoted to selling cheap cigarettes and booze to European day-trippers.

Facebook Twitter Pinterest With coach driving comes great responsibility ... Jones as Pete Green in Don’t Forget the Driver. Photograph: BBC/Sister Pictures

“This strange little world of people obsessed with themselves, and getting the best deal for themselves,” says Crouch, “seemed very rich terrain – about where we now politically – without being bludgeoningly obvious.”

“And the fact that you can go to a war memorial on the way there struck me as a very rich double-bill, which really unlocked the whole thing for me,” adds Jones. That day out ended up inspiring the show’s opening episode.

Scriptwriting duos vary between those who sit side by side at a keyboard and those who email drafts between their studies. Don’t Forget The Driver was written in one room, with delineated responsibilities. Jones describes himself as “the improviser, walker-rounder, shouter-outer, playing all the characters. And Tim is the methodical tapper-outer first draft guy.”

For Crouch, unused to the world of TV, the exhaustive vetting of scripts for potential legal or editorial infringements came as a surprise. A mention of the Regis School of Music, a nostalgic venue from his upbringing, was changed to the fictional Regis School of Dance, in case it was seen as the BBC advertising the real school. The writer had also included the names of several people from his childhood, including his first girlfriend: “But the ‘negative checkers’ came back and said, ‘You can’t have that because it’s an actual person in Bognor Regis.’ I said I thought it would be a nice nod to her, but the BBC wouldn’t have it.”

Also cut was a scene of the coach full of day-trippers returning to the UK: “The legal department said we couldn’t be explicit about how they crossed the channel. If we had them going through the Channel Tunnel or on a ferry, it might infer malpractice from the tunnel or ferry companies because they had allowed a stowaway in the coach on the way back. We lost a beautiful scene.”

As well as writing half the scripts, Jones also doubles up in the cast, playing both Pete and his Oz-based twin, Bazza, who pops up via Skype or the Bognor Regis live web-cam. Jones claims that his two-for-one performance happened accidentally: “In that first week of writing the treatment, a lot of decisions were made without really seeming to be made – give him a brother, a brother in Australia, make him a twin brother and then you can play both parts. I don’t remember ever actually agreeing to that; it was just left in.”

The Bognor-Australia conversations, says Jones, reflect a key theme of the series: “I think the implications of the digital revolution are only just beginning to be understood. The comedy of miscommunication seems to be increased by the amount of options for communication we have. That seemed to be a good way of exploring the show’s general theme … bewilderment among people.”

Don’t Forget the Driver starts on BBC Two on 9 April