Come Rain Come Shine, ITV1

David Jason’s toby jug of a face has been on the television screen over Christmas since the days when you had to get up and switch between three channels by hand. There was nothing ostensibly seasonal in his latest vehicle. A Yuletide entertainment for our times, Come Rain Come Shine had starring roles for three very contemporary ghosts of Christmas Present - belt-tightening, debt and social implosion. But scratch at the surface and what emerged was a neat inversion of the Scrooge tale, in which it was a big spender rather than a miser who had to learn the value of family.

Jason played a man whose eagerness to see the best in everyone had a tinge of Dickensian relentlessness. His son expressed the desire to punch his face (though not actually to his face). After an hour of listening to Jason spread good cheer like muck on roses you kind of wanted to follow suit. This is just a hunch, but that may well be why a drama fronted by such copperbottomed stars as Jason and Alison Steadman was not scheduled closer to the big day.

Give or take the odd body swerve, you sort of knew where this was going from the first frame. Working-class Don and Dora turned up brandishing naff plastic bags full of gifts at the swanky suburban garden party thrown by their son David (Shaun Evans) who, having made it big in property, had slithered up society's greasy pole. But in this parable about the perils of accelerated social mobility, David had soon lost everything – job, car, house. The entire fantasy scenario was built on the quicksand of credit.

The one thing he still had was his family, who uncomplainingly returned with him to cohabit with his parents on the council estate where he’d grown up. His wife Christina (Anna Wilson-Jones), initially portrayed as stuck up and acquisitive, got a job stacking shelves. His son Cameron (Drew Blackall, pictured right with Jason), taken out of private school, hawked his electronic goods at his state primary to plug a hole in the family finances. And in due course David persuaded his father to stump up £50,000 to finance a property deal by mortgaging the flat. No matter that his sister Joanne (Kellie Bright) was a single mother with two children and no support from the children’s petty-criminal father. Needless to say the prodigal son promptly lost the money, embarked on an affair and eventually managed the impossible: to remove the scales from his father’s eyes. David Jason then had the expected coronary, leaving the fractured family to heal itself at his bedside.

Jeff Pope’s script snuck in some worthwhile observations about what our new masters like to call Broken Britain. Who in the end makes a more feckless contribution to social breakdown: the stayaway father who leaves entire families sucking on the teat of the welfare state, or the social mountaineer who betters himself by borrowing beyond his means? And more specifically still, is a father who refuses to think ill of his son any less damaging a fantasist than the son who builds castles in the sky on money lent by the bank?

This was at least in part a drama for and about a generation of retirees left shaking their heads at the moral turpitude of their spawn. Tonally, though, it all felt a bit uncertain. Jason and Steadman brought with them a career–long commitment to keeping it frothy. "Oh don't!" Steadman said, just like Pam in Gavin and Stacey. With many a comedic embellishment, the script colluded in the idea that if you giggle, the world giggles with you. Thus when Dora discovered that her husband had given away their life’s savings to her son, her seething anger lasted only until the air-freshener gizmo on the bedside table exhaled a comedic little parp. The stakes never felt anything like as high as they would in actuality.

In the end there wasn’t much for anyone to do apart from Jason, who played the only character given the chance to climb out of the narrow trench dug for him by the narrative. “Be quiet, I’m talking now,” he said to his son as he prepared to deliver his big speech about money not bringing happiness and family being family. Only he’d been talking all film already.

• Watch Come Rain, Come Shine on ITV Player