It will be tortured. It will be tedious. It will be tiresome and sometimes hurtful and offensive as the tin-foil hat brigade is ushered back to centre stage to shower us with their fever dreams of the terrible things to come if we take a chance on love. It will be no fun at all. Or to put it another way: see that door? Slam your head in it half a dozen times and lie down till it's over.

"We're going to have to draw a line under this at some point," said host Tony Jones as the marriage equality section of the debate nudged the 29-minute mark, having absorbed about half the show and much of the mental energy of viewers and panelists alike. Greens leader Richard Di Natale is a cool customer but every now and then his eyes let you know he couldn't quite believe what he was hearing.

Two months back, Q&A hosted a one-off gay-themed edition with a guest host and a panel of local guests that was genuinely enriched by the presence of the Reverend Fred Nile; you can't tell the story of DIckens' A Christmas Carol without the Ghost of Christmas Past.

But for Monday night's accidental sequel, a program dominated by gay issues had three pollies - Di Natale, the Liberal Kelly O'Dwyer and Labor's Sam Dastyari - sharing desk space with two guests from abroad whose main skill was patronising anybody who opened their mouth.

Katy Faust, an American, and Brendan O'Neill, a Brit, must've thought it was Christmas, worth the long trip south to one of the few countries left in the Western world that doesn't treat their views as both a gigantic yawn or a legal anachronism.

Faust comes blessed with an interesting surname if you want to think about it, but it's her blog name that's the real TV-friendly gimmick: Ask the Bigot. No kidding. The other twist in Faust's tale is that she was raised by female same-sex parents but now spends her days campaigning against same-sex marriage and parenting.

In that ever-shrinking marketplace, where else would she be but Australia, being charming and eloquent on the face of it until you twig that she considers you a menace to happy children and stable society. To the child of gay parents, Faust says things like "thank you so much for the question" - as if they've just given her a lightbulb moment - but you soon learn the lights are still off. She bagged studies on gay parenting, urged a society based on "natural law", and even flipped a discussion about quotas for women MPs back to the gay parenting debate: "The gender balance matters in the life of a child, too," she reminded, quoting in support a certain Eric Abetz, the Liberal senator last seen tending to his Dolce & Gabbana sock collection.

Faust had her only ally in Brendan O'Neill, a British writer whose ability to get on your nerves is so pronounced that mosquitoes must find him annoying. Ricky Gervais would play this bloke in a movie.

O'Neill is a libertarian, of a stripe sometimes identified by other terms such as "Who invited him?" and "He's not sitting next to me". He wants everyone to get out of everyone else's face. "Leave me alone," is the broad philosophy, but delivered with such insistence it's like being taken hostage by an opinionated dentist.

O'Neill schtick combines a prancing shock value, an ability to talk under water and a refusal to give a s--t what anyone thinks of the results. This means he can dive headlong into debates on anything and come up with gems - such as his rejection of targets for female representation in government.

"Those women will never know for sure whether they were selected on the basis of merit or on the basis of their biology," mused O'Neill with sorrowful tone. The notion that his biology gives him the confidence never to ask himself the same question hadn't occurred, but never mind - he had a lesson for the ladies. "We need to let women go and let them make it on their own," he advised, a pat on the head only implied.

On same-sex marriage, he had but one mission: giving voice to the oppressed, the harassed and the marginalised. And he did it very well: the heterosexuals suffering under global gay rule were evocatively described: "The silencing, the sacking of people, the harassment of people, the demonisation of people who have a different view."

Won't someone think of the bakers? This was O'Neill's startling warning of what he called "the cake shop phenomenon". Listen up: that's the hazing of bakeries by militant homosexuals in countries with legal gay marriage, with innocent pastry chefs menaced: "Hey you stupid Christians, make this cake for me. And if they don't they call the police."

With contributions like this it was clear why the Q&A producers had invited this defender of the heterosexual sponge industry on to share his thoughts. Whether defending the dignity of bakers or women, O'Neill was heroic - but it took his defence of the world's put-upon politicians to really make the night.

In his aghast description: "Today, if you don't believe in gay marriage you don't have a hope in hell of getting ahead in public life."

You could hear the rest of the panel's heads about to explode at the bravado of this line, and in the far distance a long, long chuckle - Tony Abbott, the remains of marriage equality legislation rotting in the bin, was delighted to see Q&A finally getting itself some quality guests.