It's not every day that you get to see a film as ambitious in its scope as Everybody's Fine (dir Kirk Jones, 2009). Sure, we can enjoy watching Robert De Niro's mobile countenance. Here, among other expressions, he grins, looks surprised, scowls and smirks. But it's not a 'vehicle' for the famous American actor in the same way that it's not a 'vehicle' for any of the other big names it features on its credits roll. It's especially satisfying because it's something newish that we've perhaps never seen before. A coming-of-age story for the baby boomer generation.

Does anyone still remember About Schmidt with Jack Nicholson that came out in 2002? Both are road movies, too, strangely.

Franke Goode (De Niro) has never harboured special desires for happiness. For 30 years he handled a production line that placed PVC coating on telephone wire ("I coated 11,000 feet a month," he tells one young woman on a train as it forges its path through the ever-changing landscape), to support his large family. But he is given a special concession by the filmmakers. They want to work out how he can be happy now that his wife has died and his children have all left home. This is the sequel to the matinee main event, the upshot of all that happens after the lights go up and the audience makes its way out into the bright reality of the midday street. What happens, you may have wondered as you negotiated the crowd, when the perfect scenario you've just seen play out on the screen begins to crack around the edges, when the petrol gets low in the tank and it's time to pull over for a refill on the road to the next stage of life?

What happens to a man whose wife was the only conduit he has had to the dreams of his children?

Once she dies and something goes seriously wrong, how to communicate with those complex, rebellious people who once depended on you for their daily bread, and more. What happens when none of them will tell you the truth because you have never allowed them to fail? Now that you can't compel them to comply with your commands, and there's a mishap to discuss, they simply avoid all contact. They lock you out. Are you therefore a failure as a father?

Yes, it's a classic case of the emperor having no clothes. But it's engineered with enough specific detail that it has a valid centre of gravity. It works in so many, small ways. The detail is all-important, making it a pleasure to watch. If you are careful there is much to learn about the lineaments of regret in Frank's shrunken world. Rosie asks him at one point: "What about you? Didn't you have any dreams that you wanted to see come true?" "No, never," Frank replies. "I just wanted to provide for my family. Keep down a job and provide for my family."

Frank does really spend a lot of effort putting together a holiday meal for his children - who live in the far-flung metropoleis of New York (David, an artist), Chicago (Amy, an advertising executive), Seattle (Robert, who plays in an orchestra) and Las Vegas (Rosie, a dancer) - so that they can comfortably assemble for the first time since their mother's death eight months prior. It's an annual event, after all. Frank's self-important fussing at the supermarket while he buys the best cuts of meat and the best bottles of wine, and a fancy new $600 barbequeue, speak openly of the pride a man feels at the fact that he is able to support his family. It's the same pride that caused him to ignore his children's wishes, that caused him to tell David, the youngest boy, that it was not enough to be a painter - he had to be an artist. ("A painter paints walls and dogs pee on them.") The same pride that made him a good provider made him fail as a father.

And the kids don't come. One by one, they beg off travelling to the old, white-faced family home with its velour armchairs and well-cropped lawn. Devastated, he does the only responsible thing. He visits his doctor to stock up on medication for the trip he needs to make. The doctor advises him against travelling and warns him off flying. He decides to take the train and buses. Arriving in New York, he spends the night asleep on the stoop of David's apartment building because the young man is not home.

Undaunted, Frank heads for Chicago to meet with Amy (Kate Beckinsale), who lives with her son in a large, modernist-inspired house set in leafy surrounds. The house screams of vocational success but the family dinner that night is Chinese take-away and Amy's son, Jack (Lucian Maisel), is inexcusably rude to his father. Amy begs off playing host to Frank for a few days, inventing an excuse that puts the ageing King Lear back on the road the next morning. He follows it to Seattle, where he comes across Robert (Sam Rockwell) playing percussion in the local symphony orchestra.

Poor, dim Frank slips back into the same old routine. Do you smoke? You know what? I quit! I thought you were a conductor? I'm happy playing percussion, it's low stress and I get paid for it. I thought you wanted to be a conductor? Look, if it hasn't happened by now, it's never going to happen. Isn't it all wasted? What do you mean 'wasted'? There's a fantastic little scene where the unpreposessing Robert, moping around with Frank outside the theatre's stage door, introduces his father to the conductor. A moment later, the man has disappeared inside. There's time for no more than a handshake and a quick 'hello'. Robert is just the guy on drums.

This time, Frank doesn't even stay the night, but because he hasn't adjusted his watch properly he misses the train to Las Vegas. He hitches a ride with a truckie and ends up getting mugged in a train station. His medication is smashed underfoot by the feckless young derelict but Frank makes it to the city where Rosie (Drew Barrymore) picks him up in a stretch limo and takes him to a luxurious apartment that is so obviously not hers that Frank's persona visibly shrinks - once again - as he sinks to his real level in the world. His wife is no longer around to lie to him. There's nobody on hand to tell him everbody's fine.

After staying one night in Las Vegas Frank boards a plane where he has a seizure in the onboard toilet. When he lands in hospital, the children finally gather - around his sick bed, now - and the truth comes out about David's drug overdose and death in Mexico. That night, Frank dreams that David comes to his room. Words of comfort are spoken - the type of words that contain all the love, but obscure all the realities, between a father and a son. They are possibly the only words that a child, finally, can say to a parent.

Fortunately for Frank - and for us - there's a reprieve and his copious brood gathers at the white clapboard house for a Christmas lunch with all the trimmings. At the supermarket, he again fusses self-importantly at the meat counter and in the wine aisle. The bird has to be the biggest. The wine has to be the most expensive. There's a new tree to buy and it must be top-of-the-range. But, ah, the sweet pleasure when Robert admonishes him to cut the leg to make sure that it is cooked through. Oh, the exquisite delight when Rosie puts her arms around him when they bring up his wife's annual propensity to overcook the turkey.

And look! See Rosie and her new lover (the same girl with snappy black hair Frank had met briefly in that fantastic Las Vegas apartment) feed his first grandchild.