The Curse of Steptoe BBC4, 9pm
10 Days to War BBC2, 10.30pm

According to The Curse of Steptoe, in the immediate aftermath of the live studio recording of Steptoe and Son's debut edition, actor Harry H Corbett summarised the audience's reaction with a mixture of puzzlement, dismay and annoyance. "I thought they laughed a lot," Corbett gravely informed the groundbreaking TV comedy's creators, Ray Galton and Alan Simpson. The writing duo had naturally been delighted by the sound of communal chortling, whereas Corbett was used to his acting being received in reflective silence - reflecting how seriously he himself took it.

At this stage of his career, in 1962, the young Corbett was a budding Shakespearean lead working on British stage acting's cutting edge, and obsessed with his own credibility. Moreover, he was a self-obsessed method actor who revelled in being tagged "Britain's Marlon Brando," and sought to imbue every performance with authenticity, truth and proletarian grit - and, as Brian Fillis's pithy and acutely researched script for The Curse of Steptoe made plain, large measures of preening self-delusion.

Crucially, Corbett's initial perception of Steptoe and Son was wildly wrong. He refused to see it as a sitcom about the misadventures of a father-and-son rag'n'bone duo bound together in mutual loathing in London's grubby east end. Instead, he proclaimed it "practically Beckett ... tragic, kitchen sink". This was all in marked contrast to the no-nonsense showbiz trouper's approach displayed by Corbett's older screen partner, the rigidly formal Wilfrid Brambell. "I put on the costume and act," he explained simply, evincing the same scorn he poured on everything, including his own homosexuality. Mired in despair, Brambell increasingly chose to divert himself with drink and the purchase of anonymous sex from rent-boys.

Yep, if you were expecting affectionate giggles from Fillis's histoire of one of Britain's best-loved sitcoms, you'd definitely come to the wrong drama in The Curse of Steptoe. Instead, it offered a compelling and complex study in the corrosive power of self-deception and self-disgust, as well as the mortal perils of being typecast in the popular imagination.

It was also illuminated by two wondrous central performances. As Corbett the super-luvvie, Jason Isaacs was a perfect picture of cruel narcissism throughout. Portraying the jaundiced Brambell, Phil Davis curled his lip in a brilliantly acrid rictus. And when required to play the Steptoes in extracts from the TV show - young aspirational 'Arold and mocking-yet-dependent Albert - Messrs Isaacs and Davis were simply transcendent.

The equally commendable and absorbing 10 Days to War reached its climax with a punchy resumé of events that unfolded in one British Army encampment in the deserts of Kuwait on March 19, 2003 - or, in other words, one day before the beginning of Bush and Blair's misguided Anglo-American misadventure in Iraq. Kenneth Branagh cussed, chomped on a cigar stub and exuded inspiration by the bucketload in the role of Colonel Tim Collins, the brusque Ulsterman who so memorably rallied his troops in the 1st Battalion of the Royal Irish Regiment with a noble eve-of-war address ("We are going into Iraq to liberate, not to conquer").

In addition, Collins provided every wise military leader's ideal response when quizzed by a humble subordinate about why now has been chosen by far-off political idiots as the time it for an army to start doing whatever it's meant to be doing. His reply is the universal soldier's all-purpose motto: "We're doing it because we're doing it - it's what we do."