By his own admission, last time Stewart Lee played the Greenwich Comedy Festival marquee – in front of a beered-up crowd in 2010 – it was a disaster, and the gig had to be rescued by Daniel Kitson. But if he had second thoughts about returning, he slayed that demon at the opening night of this year’s event in the grounds of the National Maritime Museum, thanks to a virtuosic routine about the perceived wisdom that liberal comics wouldn’t dare tackle Islam in the same way they would lay into Christianity.

It’s a peculiar prejudice that he’s laid into before, but this extended routine – loosely based around an incident involving a woman in full niqab on the 149 bus – was a dazzling, hilarious display of manipulating audience’s sensibilities and thwarting their expectations. In turns evoking Roy Chubby Brown while defiantly telling the large sell-out crowd precisely why they are allowed to laugh because ‘I’m not an idiot and know what I’m doing.’

Indeed he does. He may have a superiority complex on stage, but he’s earned it. Under the guise of delivering the anti-Islamic stand-up he’s told people crave, he prompts examination of prejudice while taking brilliant side-swipes at the young plagiarist pretenders to his comedy crown, the crowd-sourced surveillance of Twitter, and his own reputation for pause-filled delivery. In fact, it is far more nuanced than that; for a minute or so getting laughs from hesitancy in a way not seen since Frankie Howerd’s day. It’s not all about the super-smart material – although clearly most of it is.

At the start of his headlining set, Lee promised us two routines: the called-for Islamophobia and 25 minutes entirely about urine purely, he claims, because if he heard about a comedian doing such a thing he would assume it was abysmal or brilliant – and he wanted to prove it could be neither.

He was possibly right. Even though the section was foreshortened, the fictional family catchphrases based around pee didn’t quite gain enough traction. But the mixed reaction opened the door for a masterful berating of he audience, holding us collectively responsible for real-life tragedies – with the exaggeration of blame played entirely deadpan.

Lee’s slot was prefaced by two other heroes of the alternative comedy scene, Tony Law and Josie Long, and held together with the skilful compering of ever-affable Ed Gamble. Not that he had to do too much at the start – this corner of South-East London has a fine reputation for audiences who mess with comics, thanks largely to Up The Creek and the Tunnel Club in their heydays – and the lies spun by ‘Noddy’ and ‘Big Ears’ got some instant laughs. Whether by luck or instinct, Gamble also unearthed two cops – one a police diver, the other an undercover officer who poses as a prostitute – which provided the sort of running gags any MC would hope for.

It’s fair to say the unabashed absurdity of opening act Tony Law was a tent-splitter – and he probably wouldn’t have it any other way. Playing to a much wider crowd than his natural audience, his nonsense garners huge laughs, but also some stony faces.

However anyone who comes onstage in way-too-snug onesie and carrying a trombone and a shopping bag is clearly not a comic who takes themselves too seriously, and there are gags at his own expense a plenty. He may be weird, but he’s also that archetype of the mainstream comedy ‘saying what we’re all thinking’. It’s just that what we’re all thinking is ‘that guy’s odd’ – though there’s more to his comedy than that superficial impression.

Long, like Law, performed edited highlights from her Edinburgh show, about her struggles to enter enter the successful relationship she believes she ought to have now she’s in her early thirties, especially given her inherently romantic nature. There’s a strong narrative structure to this, starting off with her stupidity in going to the wrong airport and weaving deftly around her own family and – making something of a departure for her, a sex story.

It’s not as overtly political as her reputation – save for a dark fantasy about doing away with Nigel Farage or the odd aside about the warped priorities of those who seek wealth above all else. But there’s something more subtle about reclaiming the ‘period joke’ from being an inaccurate slur against female comics. A strong ending for a warm, thoughtful, and funny routine.