How The Apprentice changed the shape of reality TV

And then there were two. Tonight, shortly before 10pm, Sir Alan Sugar will stroke his designer stubble, exhale grumpily, and answer a question that has dominated dinner-party chat for almost three months: who will be his next apprentice?

The final of the businessman's hit television show, The Apprentice, will pit Kristina Grimes, a 36-year-old single mother from Harrogate, against 27-year-old Clapham boy Simon Ambrose. During the show, they will compete to design a new "landmark" building for London's South Bank.

Whoever Sir Alan decides has done the best job will win a £100,000 one-year contract in his sprawling business empire, together with minor celebrity status and bragging rights over the 15 other hopefuls who entered the knockout contest in March.

Despite the contempt in which our ruling and chattering classes hold " reality television", however, The Apprentice has shown that the genre can attract an intelligent, middle-class audience.

Following its move from BBC2 to BBC1 for this, its third series, The Apprentice has become a weekly talking-point for Britain's chattering classes. The show has attracted up to six million viewers (up from 4.5 million during its last run) and turned some of its stars into bankable celebrities.

We have Margaret Mountford and Nick Hewer, Sugar's sidekicks and official eyes and ears, who assess his contestants during entrepreneurial weekly tasks that involve anything from selling English food at a French farmers' market to making a television advert for a pair of trainers.

Or there's the contestant Tre, a sweary and somewhat misogynistic Essex boy with a peculiar beard, who boasts a talent for self-aggrandisement and a knack of falling out very colourfully with most of his fellow contestants. He's become a sort of cult icon.

And what more can be said about the Miss Piggy-lookalike, Katie Hopkins? She's a man-eating posh girl from Exeter who, in no particular order, has seduced a fellow contestant, insulted most of her rivals, and run off with someone's husband. Since leaving the show, she's been photographed making love to a third squeeze in a field, and sold her story to the News of the World.

Since its launch in 2005, adapted from an American version fronted by Donald Trump,The Apprentice's greatest legacy has been to kick-start the fad for television entrepreneurship, inspiring shows such as Dragons' Den and Risking It All.

The show's underlying theme, that "greed is good", has inspired supportive statements from the Confederation of British Industry, and glowing profiles in The Spectator and The Economist. Where shows such as Big Brother provide brain candy for morons, people who count take The Apprentice seriously.

So great is the interest in the show's outcome that two versions of the ending of its final episode have been recorded: one where Kristina wins, and one where Simon triumphs. The contestants learnt of their fate during a top-secret lunch with Sir Alan yesterday.

In the run-up to their big moment, The Independent provided the finalists with their trickiest task yet. Both, naturally, proved adept at selling themselves. But could they cast their burning ambition aside, and sell each other?

Kristina on Simon

Kristina Grimes is a 36-year-old pharmaceutical sales manager from Ireland who lives in Harrogate. She went to university after becoming a single mother at a young age. During the series, she was a no-nonsense operator, but clashed occasionally with Katie Hopkins.

"Simon has to stand up and prove himself. He'd be the first person to say he hasn't really knuckled down and focused on one thing in life yet, but maybe that's because he's determined to find the right thing, and not settle for second best.

"If I was a manager looking at his CV, I would have concerns. He is at the age that if he carried on drifting around any more then he'd start suffering lost opportunities. If I hadn't had a mouth to feed at that age, I'd also have played about, and gone off travelling.

"Simon is enthusiastic. He likes to be around people, to be involved and have fun. He can also be a clown, but that can be a good thing. The rapping certainly made him look like a plonker, but then his team won in the end. You shouldn't always jump in feet first, because one day something will bite you on the bum; but he's 27 years old, and will grow up.

"When we were interviewed, Simon really did his research and it paid off. It was a smart move. Whereas the rest of us pretty much scored in and around the same as each other, he was the one person that stood out. That wasn't a bad thing. He also speaks six languages. Is that important? Well, we live in a global economy, but everyone speaks English. We've got the monopoly on it. However, I think at end of day it is an extra skill. It could be valuable or could be irrelevant. It's not a definite advantage, but might help him in future roles.

"Simon was always out there and getting noticed because he loved being in the limelight and always made sure there was something funny or quirky about him. That's Simon. He likes being the centre of attention. He can be annoying, but he's also bright and articulate, and can hold your attention. They are great assets for a business.

"I never looked at him and thought he was the one to beat, but I was so focused during filming that I was like a bull in a china shop. Nothing that could distract me. That mentality has kept me focused and made me successful thoughout my career. Now I've finished filming, though, I'm not as focused, and would say that he definitely stood out from the crowd."

Simon on Kristina

Simon Ambrose is a 27-year-old internet entrepreneur from Clapham. After gaining an economics degree, he joined - and was later fired from - a bank. During an episode in which teams had to make an advert, he distinguished himself by performing a rap.

"Kristina and I never actually worked together, because we were always in opposite teams, but I've been around her enough to know that she's a formidable character: ruthless, intelligent, unassuming. She hasn't got bias. She doesn't judge people. She's got a very open mind, but she's determined, stubborn as a mule, and will always see something through.

"Away from the cameras, Kristina's a team player and has been very intelligent in that she didn't let herself fall into the trap of getting too pally with people. She's always kept it professional and didn't lower her guard, and jump into bed, so to speak, with other characters.

"We've been living in a hothouse, so tempers have flared, and there have been emotional moments. Kristina did very well to keep out of all of that. Everything's fed back to Sir Alan. He's plugged in to what goes on, and it will not be lost on him that Kristina didn't lose her cool, or backbite.

"Being a single mother should be taken on its own merits: you've got some soft ones, some disorganised ones, and some very happy ones. It's a wonderful testament to Kristina's steely resolve that she's a fantastic mother, but also a very able businesswoman. She's had her wee bairn and isn't going to have another, so there are no worries for a potential employer such as you might get with other women in their thirties.

"As for her CV, getting on in pharmaceuticals is no mean feat. It's a very technical, specialised industry and you really need to know your products to get ahead in it. You need to know the tests and the phases. There's a lot more than what it says on the tin. It's not just a simple sales job.

"Looking at what happened with Katie, I don't think she necessarily fell out with her. If you look at tasks where they worked together, they got on and did the job. On the buying task, they were paired up, and were major, major contributors to the fact that their team got on and won that task.

"Back in week 10, I picked myself, Kristina and Katie as the three people who would be there at the end, and I think Kristina deserved to get to the final on merit. She wants the job far more than Katie, who had different agenda and motives for doing this show. Kristina, on the other hand, is an obvious choice, who sells herself."