FORD Kiernan and Greg Hemphill are sitting across the café table, sipping coffee and laughing hard about death. Yes, death. And you’d be right to wonder why that is the case. How much comedy leverage is there in theme of our chat: ‘When is death a binary state?’.

You don’t often interview the Still Game creators and find yourself saying, ‘End of life is permanent. So does theatre license allow for the natural laws of biology and function to be subverted?’

The grim reaper conversation is relevant, however, as we sit in the Sky Bar, on the 9th floor of a Glasgow hotel, an entirely apposite vantage point because the pair are on top of the comedy world as they look down on the SSE Hydro, where they will be appearing in Still Game: the Final Farewell in 20 days time.

Yet, how can Jack and Victor appear on stage nightly before 10,000 committed fans when they are deceased, gone to the Clansman in the sky. Forever. Finished.

Didn’t the very last episode in the final TV series end with the pair reflecting on the end of their lives, walking up a mountain in the direction of Hopelessness and never coming back down?

“Are we deid?” says Kiernan, rhetorically, grinning like a schoolboy who’s found the answers to the biology exam, and won’t pass them round. “Yes, we are. But here’s the question; what really happened when we walked up that hill? Yes, there has been lots of speculation. . . . and that’s the idea for the show.”

So far this premise is as clear as the mist which engulfed the freezing mountain on the day the pensioner pals took their final trek, dressed in their usual cardie and slacks outfits. Hemphill steps in to help the confused interviewer see the way ahead. “There was actually an unconscious seed planted for the plot line of Jack and Victor going up the hill back in series four,” he recalls. “There is a line in one episode in which Winston is talking about the Comanche idea of when you get to a certain age when you decide it’s time to take the long walk away from the village. We’d forgotten all about that.”

Great, Greg. But did Jack and Victor walk off to die? Had you killed them off? “No, we hadn’t killed them off,” he adds. “The point of seeing Boaby in older life is to let you know they are no longer there, but that’s because it was a natural life span.”

Kiernan nods in agreement then adds: “We never killed Boaby because that would be a crime to kill him off in the prime of all his boabyness, whereas the others had been around the block.”

The Still Game pair look at the still clueless face across the table and break into grins like a couple of Sixties hippies who’ve overdosed on hash cookies. I get it. No spoilers. That makes sense. We all want to go to the Hydro and see what they’ve come up with to explain the return of J&V. But can you add a little plot detail? Kiernan offers a little light. “Well, if you’re a fan of Chewin’ The Fat there will be a couple of wee Easter eggs in there for you.” Hemphill slides in. “We’ve been together 20-odd years so we want to reference that.”

Gosh. Could that mean the likes of the Banter Boys mincing onto the Hydro stage? Or an appearance from the hapless thespian Ronald Villiers? “Who knows?” says Hemphill, teasingly. Kiernan laughs. “Mibbe no’ Ronald. He’s such a clown. He’d probably show up at the Pavilion.”

Hemphill does add a note: “The show is set in the now. It’s not a flashback to a young Jack and Victor story.”

That takes conversation onto less opaque ground. What of the future of Still Game? Viewers are desperate to know whether they will continue to entertain us. Will Jack and Victor appear on-screen again in some form? Has the idea of time travel been considered, whereby the pair are seen as younger men? Pay dirt.

“Well, that question has been asked of us recently by a couple of head commissioners from the BBC,” says Kiernan in upbeat voice. “They pointed out that when we did the retro Christmas episode (2006) that it got some of the highest ratings ever. And they wondered if that was something we would be interested in.”

Sounds great. The watching world would love, perhaps, to see an expanded Christmas show in which we meet Jack and Victor as younger men. However, Hemphill seems to humbug the notion. “The idea has been talked about. And of course a younger version of Only Fools and Horses was made. But I sort of think, personally, that the comedic strength of Jack and Victor was their age.”

What of spin-off potential? Could we see Still Game characters fronting their own shows? “Yes, that has possibility,” says Kiernan. Featuring whom? Boaby? Isa? Navid? Hemphill joins in. “I’d love to see a Christmas special with Boaby or Isa. But things are up in the air.” He adds, in less ebullient voice, “And we’ve had our comeback. It’s now time to step back.”

There are mixed signals being broadcast from the comedy pals. They both agree they are focused on making the Hydro show an extravaganza, but when talking of the future it’s hard to see the plan. “I’m not being coy to say I don’t know, but that’s how it works in the business,” says Hemphill. “We’ll have conversations in the next few months.” Does he want to pursue his interest in film, in directing, which he’s revealed with BBC Scotland in recent years? “For sure, but you’ve got to make that happen, make yourself available. And Still Game the TV series has taken up six months of every year.”

Kiernan agrees the Still Game success has been curtailing. “We’ve both missed out on acting jobs because of the commitment. There are a couple of films being made here that my agent didn’t put me up for, and some touring theatre offers, because of Still Game. That’s been the case for a few years.”

If writing Still Game has been so time consuming, have they considered following the American model with writers' rooms, whereby a spin-off series could run under their aegis? “Both of us are hotly interested in the writers' room scenario,” says Kiernan, his eyes open wide enough to suggest this is a real possibility. “I think that’s the future.”

However, Hemphill’s eyelids are a little more Garfield. “Writers' rooms work well in the States whereby a broadcaster will order lots of episodes. But the financial structure here isn’t set up that way. The BBC and ITV tends to commission in terms of six episodes which lends itself to the singular writers.” But what if Netflix or Amazon came along and asked for 26? Would you get on the phone to writer pals and invite them on board? “I like team writing,” enthuses Kiernan. “I loved being in the writers' room when we worked on Pulp Video. It’s an idea that can work.”

Could casting change? “Do I think Jack and Victor could be played by other actors? Yes, I do,” says Hemphill. “And in five years' time you could get a new audience.”

Kiernan agrees. “It could be great to see two new actors come in. That’s something we could think about. Maybe in five years it would be great to see two 28 year-olds play us.”

Yet, if there are no immediate plans to re-boot Still Game, or create a spin-off, what’s going to give you boys a reason to get out of bed in the morning? You’ve both loved/craved a challenge going back to the days of stand-up, in theatre, back to the early days of Pulp Video sketch comedy.

And what of your relationship? Courting took you to the Edinburgh Festival in 1997 with the very first stage show and the writing marriage saw you conceive not only Chewin’ The Fat and Still Game, but produce other offspring along the way such as Happy Hallidays and Dear Green Place.

You divorced in 2008, amidst a little acrimony, yet moved back in together to your writing room in Byres Road and the relationship produced three more TV series and three incredibly beautiful Hydro-born children with names such as Bank It, Bonanza and Bonus Ball.

But what will happen after the night of the last-ever Still Game theatre show? Will you get together next week and throw around ideas? Will the writing relationship become an occasional hook-up, sex-on-a-Saturday-night situation? “Yes,” says Hemphill, laughing. “That could be it. And no phone call on a Sunday morning to say ‘That was nice, wasn’t it.’”

Kiernan joins in. ‘Aye, no’ even a mention of getting a pizza during the week.’”

Or perhaps you might take to Tinder, in a professional sense, and partner up with someone else? Hemphill says he isn’t sure. “There isn’t really a plan. We’ll meet up in the New Year and see what happens then.”

Kiernan concurs. “We need time to bed in the idea that we’re finished.”

Yet, both of you will miss the connection. The being together. You won’t want to spend your time on a yacht in the Bahamas, will you Greg? “You’re right. When people stop working they struggle with the loss of camaraderie.” This time, however, it’s Kiernan who makes light of the impending split. “Rikki Fulton once said, ‘I miss the days of Francie and Jackie’. Someone said ‘Don’t you mean Josie?’ Oh yes, Josie.’”

There’s little doubt Ford Kiernan, born in the East End of Glasgow, and Greg Hemphill, who grew up in Montreal, are two different creatures. Kiernan more business focused, the driver, the big energy, keen to conquer the world. Hemphill has been more contemplative, happier to write at his own pace, keen to direct and become an auteur. Does Kiernan believe that had they come from the same background the comedy relationship would have developed in the same way? “No, I’d have moved,” he says laughing and Hemphill laughs too, adding, “I agree. I’d have looked at where he lived and said, ‘This place is way too rough for me. I don’t fit in here!’”

The riff continues. Kiernan nods in the direction of his partner and adds: “I used to say to him, ‘I never had a gate in my house, but not only did you have a gate, your da’ used to operate it electronically.’” Hemphill joins in. “And I’d say to him he was one of those snottery weans in the Oscar Marzaroli photographs, playing amongst the bricks outside the tenement.”

Kiernan bellows: “He had a front door. We burnt ours to stay warm! And I saw him as a boy in the Canadian wilds, with a rifle and a bear in tow. (Canadian accent) ‘Let’s go get our dinner.”

But if the differences helped them create great comedy, they’re now defined enough to push them apart, at least until they come to miss each other.

For the moment, however, they are set to produce a major theatre finale. “It’s not really about the money. It’s about an incredible experience. It’s about an atmosphere in a theatre generated by 10,000 people, which is more than five times larger than that of the King’s Theatre. It’s the idea of doing something so different from a half-hour sitcom. It’s about appearing before an audience who have been so amazing about accepting this concept, this size, yet still enjoying the intimacy of Still Game on television.”

Hemphill concurs. “The Hydro has been great for us, and the audience. We want to make this final show really special.”

What seems certain is Jack and Victor will never become two chalk lines on a pavement. They will re-emerge, somehow, sometime. As for Kiernan and Hemphill, they’ll walk down a road together at times. But I don’t sense they will still be holding hands.

Still Game: The Final Farewell, the SSE Hydro September 27 – October 13. Tickets still available.