Wembley Arena, London Though the timing is spot-on, the comedian’s outrageous swipes at every sexuality, race and even disability descend to cliche as their wickedness exceeds their wit

It’s a big night for Bianca del Rio, breakout star of RuPaul’s Drag Race and the first draq queen to headline Wembley Arena. And she’s celebrating the occasion by being unspeakably vicious about everybody. Of course, Del Rio isn’t the first drag act to flout propriety. But Bianca really puts the outré into outrégeous, with 75 minutes of comedy mocking straights, “faggots” and lesbians, midgets, “fat girls” and people with Down’s Syndrome too.

Which is fine, as far as it goes. No one group can claim to have been singled out for abuse – and Del Rio takes pains to reserve some harsh words for herself. Her hate speech is in any case just for flamboyant fun, right? Nothing about Roy Haylock’s alter ego invites us to take her seriously, from the “clown in a dress” stylings, via her wicked way with a side-eye and a swig of white wine, to the running joke about “my best friend” representing whichever minority she’s just dissed.

Drag is low in the mix: Del Rio’s faux-femininity barely figures. But Haylock is a stellar performer; his comic timing is spot-on. And his neck couldn’t be brassier: in the post-show Q&A, he’s startlingly mean to members of his audience.

Facebook Twitter Pinterest Del Rio is the first drag queen to headline Wembley Arena.

But the appearance of wit – which Haylock has mastered – is no substitute for the substance. It’s fine for Del Rio to be unpleasant about everybody, but I wish she’d find new ways to do it. Instead, cliche is piled upon stereotype, as Jewish people are branded penny-pinchers, “Asians” mocked for having squinty eyes and eating dogs – and the vagina execrated as a site of bilious disgust. There are also some awfully weak punchlines, which Del Rio fails to conceal by squawking them all as loudly as possible.

I found the wickedness a bit self-congratulatory too, as her change-the-subject catchphrase (“Fun fact…!”) is repeatedly deployed to advertise the outrageousness of whatever’s just been said. Others will differ: I sat next to a man helpless with laughter at Del Rio’s every gesture and tart aside. For my part, I’d happily swap a little of the performative hatefulness for insight, honesty or good jokes.

• At Olympia theatre, Dublin, 23 September; SSE Arena, Belfast, 24 September. And touring.