As Mortimer and Whitehouse: Gone Fishing returns to BBC Two, Danielle de Wolfe learns more about the therapeutic nature of angling from the comic duo.

When comedians Bob Mortimer and Paul Whitehouse pick up their rods and descend on the British countryside to film their acclaimed angling show Mortimer And Whitehouse: Gone Fishing, the concept of solitude well and truly goes out of the window.

Returning to our screens for a fourth series, the BBC Two show sees meandering conversations descending into comedic tableaus filled with petty bickering.

It's every inch the case of two old friends putting the world to rights.

"I got so angry with him when he lost that sea trout!" exclaims Whitehouse, 63, best known for his comedic roles in The Fast Show and The Death Of Stalin.

Referring to an occasion during filming when Mortimer, 62, caught a suitably impressive fish only to let it slip from his grasp, the conversation suddenly descends into a frenzied back and forth between the pair.

"I was livid! I'd sometimes pretend I was angry with him, but when I turned around to see this idiot winding like that with this extraordinary fish..." Whitehouse exhales deeply, as if to emphasise his disdain.

"Well, I let it have a little swim first," retorts Mortimer, feigning innocence.

"But it's such a prize to catch something like that in the sea," continues Whitehouse with vigour. "It's basic, Bob. If you wind right, if you wind it in so that there's only that much line on the end and your rod is 10 feet tall, you can draw the fish in for me to get."

With Whitehouse boasting an encyclopaedic knowledge of angling and Mortimer stepping up as head chef and location scout, the show becomes something of a skill exchange between the pair.

"Fishing gives us the opportunity to go to beautiful places and reflect on life," says Whitehouse. "There are many other pursuits you could do, but for us it works because it's been my passion and it's something that Bob has always wanted to do. Fishing, it's just fantastic!"

And with filming locations encompassing North Uist in the Outer Hebrides, the Norfolk Broads and scores of picturesque locations in between, the show stands as testament to the idyllic nature of the British landscape.

Continuing to emphasise the "calming" nature of fishing, the series touches on both the physical and mental benefits of the sport in relation to the pair's own health scares.

"We had to both deal with heart problems - mine was a lot less serious than Bob's," says Whitehouse, referring to his co-star's recent heart surgery.

"It was never our intention to do one of these books which are like misery memoirs," affirms Mortimer, best known for starring alongside comedian Vic Reeves in Bang, Bang, It's Reeves And Mortimer. "All we wanted to say, really, was that if you've got heart problems, it's not the end."

"I think I felt that as well," says Whitehouse. "But, in fact, I think the newest episode ticks that box totally. The Christmas episode was lovely and quite poignant, but I felt it would be nice to start the new series with a slight change in direction, and I think it's such a happy, bountiful sort of episode because the landscape is so extraordinary."

"We don't want to be seen as the two dawdling blokes, right? - we've done some fishing, now let's moan a bit. You definitely don't want it to be too formulaic."

And formulaic they're not, as the improvised nature of the show sees the pair tackle all manner of conversations from the comfort of dry land. With viewers being a fly on the wall to their friendship, the series also sees all manner of in-jokes thrown into the mix.

"Because we don't have any script preparation, we come up with a funny set-piece that might make us laugh the night before," says Whitehouse.

"We have a guideline and maybe a very vague theme, but, I mean, I don't recognise the themes that we have half the time. Poor old Bob has a few questions to ask me which I try my best to ignore or answer with one word."

Referring to a long-running joke involving Mortimer's regimented coffee-drinking routine, Whitehouse describes the way in which he has tried (and failed) to sneak the astute observation into the script over the course of four series.

"He goes 'I have a cup of tea. And then within an hour, I have a cup of coffee. But if I don't have a cup of coffee within an hour, I don't have it at all'," chuckles Whitehouse, imitating his co-star.

"And I thought this was so fascinating that I get him on it every time. I do an Australian TV bloke going 'Can we get a camera on this? This is absolutely riveting!'

"We do it every episode and it's been on the edit room floor every week."

- The new series of Mortimer And Whitehouse: Gone Fishing begins on BBC Two on Sunday August 29.