It may have started with that exploding dog in a Kurdistan minefield. Or the ineptly bugged phone in Tehran that connected me to a chatty Revolutionary Guard. Or the rather alarming warriors in Somalia who demanded that we judge their poetry contest. It definitely started with all those improbable things that happen to journalists on the road and are then embroidered in the bar. But it ended with me crouched in a ditch in the African bush at midnight, helping to propel a flak-jacketed actor out of a steep foxhole on the shout of “Action”, as cameras rolled and government and rebel forces had a firefight over our heads.

Happily, we were filming in peaceful Tanzania, the perfect setting for a comedy about parachuting into a small civil war in Africa — just enough dead to get the news desk interested. Written with the comedy producer Jon Rolph, Taking the Flak is drawn from my experiences as a journalist in Africa and from Jon’s fertile imagination.

Staging a fictional civil war, however, can be trickier than covering a real one. Following BBC health-and-safety rules in wild Africa is a lot more difficult with a large cast and crew than with a small news team that can move rapidly in tricky situations, is trained for hostile environments and has no expectations about catering or costume continuity. And, ironically for a series about journalists in an African conflict, we had to leave our original location in Kenya because of real fighting when the post-election violence erupted. The only BBC people filming were my former news colleagues, wearing real flak jackets, not the ones stuffed with cotton that our actors sported.

Taking the Flak moved across the border to Tanzania and became the first feature film to shoot there since Hatari!, John Wayne’s deeply forgettable 1962 action film about catching wild game for zoos. One of the rhinos gored an actor in an action scene, and the script was rewritten around the incident. BBC health-and-safety regulations would never have let that happen. Our production manager maintained a rhino-free set at all times.

Making a dark comedy about intelligent, if dysfunctional, journalists means getting it right: using the real tools of the trade and creating believable characters. Our props were indeed genuine, and had even seen action — semi-broken news cameras, a burnt-out satellite dish and torn flak jackets. One BBC cameraman contributed his kit bag, “still covered with the dust of Afghanistan”, which saved the art department a bit of labour. But it wasn’t just the kit that gave our actors their authentically casual authority of veteran journos.

“The cameraman is like the drummer in the band. And he always gets the girl,” suggested the actor Damian O’Hare before rehearsals. He went into training with Darren “DC” Conway as his mentor. DC has won awards for covering conflicts and, true to the stereotype, is never short of female company. Under DC’s tuition, Damian was soon brandishing his camera with a quiet swagger.

The Canadian actor Sean Power, who plays the cameraman to Ruby Wax’s terrifying American journalist in episode two, became adept at shooting skills. “I am going to take this up for real, it’s steadier work than acting,” he mused as he shouldered his camera into a scene where rival news teams try to snag the best talking head in the village. Sorting fiction from reality became tricky as the two acting cameras were being filmed by two real ones, and village extras were being played by actual villagers. The chickens and goats ignored us all.

Actors learn the lives of their characters, not just their lines. Doon MacKichan, of Smack the Pony fame, plays a pushy and resourceful producer. To channel her character, she spent time in the production gallery at Television Centre, studied Kate Adie’s memoirs and got into the habit of requisitioning accessories she believed a news producer would carry in the field. Which is how I lost my bag full of old boarding passes, several notebooks and a hat.

The cast turned into news addicts and discussed the nightly news in astonishing detail in rehearsals — not the story, but the body language, scripts and camera­work. Martin Jarvis, who plays the big-beast correspondent David Bradburn, even debriefed Jeremy Bowen on doing pieces to camera on all those foreign rooftops.

Bruce Mackinnon, in the role of a local stringer, Harry Chambers, got his tips from the BBC correspondent Adam Mynott, in Kenya, who confided to him the many ways stringers, who are only paid per story, protect their contacts from being plundered by marauding London colleagues. Phone numbers are changed, a less than adequate fixer is hired and road directions are somehow wrong. As I hovered within earshot, several mysterious incidents from past news stories became clear.

As all journalists know, having an important story to tell doesn’t guarantee a place on the news. A misbehaving celebrity can knock a refugee camp seething with cholera off the running order. Enter the desk producers back at base, who regale dazed journalists in the field with their interpretation of events: “the way we see it here” or “the mood of the meeting was” — the last thing you want to hear in a war zone as you sit in a hotel room where the only running water is coming down the wall.

Listening to these tales, Harry Lloyd requested work experience in the BBC newsroom when he was cast as young Alex, a desk editor with a shaky grasp of geography and a degree in media studies. Harry proved a big hit, and ended up editing the lead story of the day with a senior producer.

On all levels, a happy confusion between fiction and reality seemed part of Taking the Flak. Back in Tanzania, the police ignored our “action vehicles” kitted out with fictional firepower and numberplates from an invented African nation. On set, bemused Masai warriors watched our actors and sometimes wandered into shot in all their finery, causing a certain amount of confusion, as they were extras in other scenes. And when the Hollywood star Will Smith arrived in town on a charity visit, everyone assumed he was part of the cast. One of our Kenyan actors asked me which part Smith was playing. I couldn’t resist. “Just a background extra.” True to form, a few hours later, Smith’s entourage drove into shot on a road about to be taken by our “rebels”.

Taking the Flak starts on BBC2 on Wednesday

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