Imagine how different it could have been if the young Bertie Ahern had gone along with some of his friends and joined the IRA. He thinks he maybe would have if he hadn't come from such a strong Fianna Fail household. There seemed to be a passionate tremble in his voice when he talked about the unrest of 1972. "I was there for those nights with my brothers and my friends," he says.

Of course, Bertie came from a strongly republican family, a family that was very bitter about the two years their father had spent interned in the Curragh. In 1972, Bertie Ahern held uncompromising views about the North. "Brits Out" views. He regarded the Northern entity as something that had failed. But luckily for him, and for the country, a year beforehand, in 1971, Bertie Ahern had quietly joined Fianna Fail, and he had plans to shake things up in the party.

As his colleagues, his friends, and even his own family tell you, no one really knows Bertie Ahern. But after watching Bertie, the four-part TV biopic of Ahern, you might know a little bit more about how you don't know him. The show is also a gripping drama about a gang of young fellahs who knew each other through sport, and who set out to run the country and succeeded. It's a love story too, about the woman and the family who were neglected in favour of work; about the other woman, who came between the hero and his band of brothers. And ultimately it's a story about loneliness. As one friend puts it, the only one who knows Bertie is himself and even then, when he looks in the mirror, he asks himself, "Can I trust you?" This is all set against a heady backdrop of political intrigue, public unrest and the rises and falls of great men. And Mint productions weren't afraid to play it for drama.

And then, somewhere in episode two, they had to get all politically correct and we get the tribunal stuff. So they wheel in discredited activist Frank Connolly and they start trotting out figures and exchange rates and so on. And suddenly it's time to go and make a cup of tea. In terms of content and visuals and insight, the dig-out stuff is a huge turn off. It's like going from watching a George Best biopic to watching Open University bookkeeping 101. And when the show had so much light to shine on other areas, it's a shame they felt the need to trot out a kind of potted version of the tribunal stuff. Because they had no new light to shine on it -- just Frank Connolly getting another outing from the story that has sustained him for the last few years.

Besides which, the whole dig-out stuff had been neutralised, right at the beginning, by Matt Cooper. Cooper has been one of Ahern's fiercest critics. But very early on in proceedings Cooper is there quoting one of Ahern's fiercest supporters. Cooper very clearly and deliberately uses the Eoghan Harris line that if Bertie Ahern took money from people it was for political purposes, to feed his election machine. "All of Bertie Ahern's life was political," Cooper says, "all the money that went to his accounts was for his political benefit. In Bertie Ahern's life," Cooper says, "there's no difference between the personal and the political."

This is perhaps the greatest truth of the programme in a nutshell: Ahern's complete sublimation of any personal life for politics. Cooper's point also does away with any need to get into the boring nitty-gritty of Ahern's bank accounts.

It's a pity Mint didn't just stick with the epic, compelling tale they had. I haven't seen the third or fourth episodes but one can only hope that it doesn't get completely bogged down in Frank Connolly's agenda at the expense of telling the real stories of Bertie Ahern.

There is, for example, the story of the gang. When Bertie Ahern quietly joined Fianna Fail he had that gang, of sporting buddies, around him. "We were physical guys. We were able to handle ourselves," is Bertie's modest summation of him and his footballing mates. Bertie apparently didn't look for trouble but if he got into trouble he could handle himself and maybe, just maybe, he had a bit of a reputation as a tough guy. This same gang would surround him as he went into politics, getting added to the ticket for the 1977 general election at the last minute. The 25-year-old Ahern shouldn't have had a hope against Jim Tunney "The Yellow Rose of Finglas" and local councillor Danny Bell. But that was before anyone knew about the machine Ahern had quietly built around him and his gang. "I think Jim thought we were nice guys at the start, but at the end it was very different," Bertie laughs. This kind of vaguely threatening, laddish, kind of Oasis-y air surrounds a lot of the coverage of Bertie and the guys who would be christened the Drumcondra Mafia by Charlie Haughey.

To everyone's amazement Ahern swept in as part of Fianna Fail's landslide in 1977. Even then though, no one paid him much attention. As Charlie McCreevy said: "He was just part of the crowd. He didn't impinge on the consciousness of most people." But just months after that first election victory Ahern's gang got together in Malahide to formulate a plan as to how Bertie could become Taoiseach in 20 years.

And then the roller coaster begins and the programme provides a rivetting account of the other great Ahern story -- of the amazing, unknowable operator: always underestimated but always a few steps ahead of everyone else; always playing his cards close to his chest; always with his own team of loyalists who put Ahern first and the party a somewhat distant second.

The worst that anyone in the show says about Ahern politically is that he was pragmatic and a survivor. There are bitchy voices in there like Alan Dukes and Mary O'Rourke. But rather than anyone suggesting that Bertie actually screwed over his enemies, the strongest allegation is that Ahern sometimes didn't do enough to protect people. So when Albert Reynolds's position became untenable after the Harry Whelehan/Brendan Smith scandal, there are mutterings that Bertie could have done more to keep the government going. Similarly, when Brian Lenihan lost the presidential election, largely down to his own cock-up on the phone calls to the Aras issue, Mary O'Rourke says that she "never felt (Bertie) was fully behind Brian. I'm sure he pulled out all the stops but we never felt it or saw the evidence of it." It's all very vague, all very circumstantial stuff.

The one thing we can take for certain from the show is that part of Ahern's pragmatism and survival was down to keeping his own counsel. For example, with the arrival of the Haughey era, Fianna Fail was plunged into a bitter civil war and Ahern became chief whip. But even then colleagues remember that he managed to hide his own views on the whole thing. Charlie McCreevy remembers how in all the heaves of that time Bertie never made a public comment that would antagonise anyone. In fact, McCreevy seems to think Bertie never even spoke at any parliamentary party meetings during that time.

Bertie's own daughter Cecelia had an even more insightful take on her father's unknowability. "Ask him a question," she says smiling, "and he can talk for ages, and right there and then you will believe he has spent a good 10 minutes sharing his feelings with you, but he hasn't. It's the way he is. I don't know if he's withholding anything. It's just the way he is." It seems that like trying to negotiate with his predecessor Dev, trying to know Bertie, even for his own family, is a bit like trying to pick up mercury with a fork.

According to the programme, Bertie was equally elusive when his marriage fell apart and he began his relationship with Celia Larkin. His brother Maurice remembers that when Bertie was Lord Mayor of Dublin, Maurice mentioned the fact that Celia was always around and Bertie assured him that they were all part of the group so it wasn't unusual for someone to be around. "I kept my counsel to myself after that," Maurice says.

Celia, who doesn't appear in the show, was clearly a source of conflict within Ahern's group. Her friend Michael Roynane asserts that she built up the constituency office, organised it, put systems in place, computerised it and was very important to the organisation. Yet when her importance to the operation is put to Bertie's buddy Chris Wall, he just looks at the camera and says "No".

Another pal, Paddy Duffy, goes even further: "I would say the majority of us wouldn't have been that mad about her. In the social circle at times it could be quite tense and difficult. She had staked her claim, this was her space, and basically people had to skirt around that." Royston Brady goes even further: "She just called the shots and that was it. He did what he was told."

Paddy Duffy also speaks at the group's shock at then finding out that the nature of Ahern and Larkin's relationship had changed to something more serious. Part of the shock, he says, was that they were never told. Ahern himself says of his split with Miriam: "It was traumatic for everyone; traumatic for me and for those close to you and you just did your best."

Unlike Celia Larkin, Miriam Ahern does appear in the show and is very gracious and loyal about Bertie: she still speaks, almost lovingly, about how she fell for him, how she was very attracted to him straight away, how he has "lovely eyes -- I think everyone agrees on that -- and wild hair". Of the break up she says: "I was very happy for him to get the recognition. To be Lord Mayor of Dublin was a great honour and then to be Minister for Labour -- again in Dail terms was furthering his career. But it was a time I was also very disappointed in him. He seemed to withdraw from family life and from me and I didn't really understand that. It was really a difficult time."

We don't get a great understanding of it ourselves either. There is no suggestion that it was a great passion that tore Bertie away from his family, who he still seems to love. If anything it seems that Bertie's family was just another victim of that life Matt Cooper talked about, a life that had no personal, that was all political. It sounds from what his family and friends say in the programme that in leaving his family Bertie was not indulging his own needs above those of others, it was just another example of how he didn't look after his own needs. Life was political, life was work, and Celia was part of that life so he ended up with her almost by accident.

One never gets the impression in the programme that he would have passionately and romantically pursued Celia. Maybe it was a case of, in Royston Brady's words, Bertie just doing what he was told. His own explanation is: "In any life, when you're working a lot of hours, when you're not home, when your concentration is always with something else, when you're not giving your best to your own life, you get into difficulties and that's inevitable."

So perhaps, like Ahern himself, Bertie, or at least parts one and two of it, is a flawed masterpiece. When the storytelling is real and human and focuses on the real world that Ahern inhabited it is a thrilling story of the last 30 years of Irish life. But a bit like Bertie, when it gets bogged down in figures, figures that we have already trawled over hundreds of times, it loses us. Frank Connolly is also one of the most singularly un-televisual individuals I've ever witnessed, devoid of any charm, charisma or magnetism.

Unlike Bertie, who, as Olivia O'Leary points out, made a career out of being underestimated. He still is underestimated by many people. Ahern said he would let history judge him and I think as a first draft of history this programme could go some way towards explaining the meaning of this extraordinary man, this phenomenon. But it is probably best to reserve judgment until we've seen episodes three and four. One way or another, this is unmissable TV.