Bang! The race is on. James Graham is the celebrated author of This House, a superb examination of Labour’s administrative bellyflops during the 1970s, which premièred at the National last year. Some time ago, Graham was asked to update his 2008 play, Tory Boyz, about homosexuality in the Conservative party. Over the same period, the Tories have been furiously updating themselves. Who will embrace the future first?

Graham’s play is a blend of then and now. He imagines an openly gay youngster working in the Tory policy unit, and he compares his experience with Ted Heath’s career in the 1950s. (That Heath was gay is taken for granted.) But the sprint is over before it’s even begun. Graham’s reworked script hasn’t the legs to outpace the Tory modernisers who earlier this year legalised gay marriage. This befuddles the play’s purpose.

Graham attempts to dramatise the travails of his gay character by inventing a swaggering Conservative bully who humiliates his colleagues and mocks their sexuality with barrages of loathsome jibes. It’s scarcely credible that such a figure could exist today, let alone escape detection. His brand of vicious bigotry would be secretly recorded and broadcast on Channel 4 in a sensational exposé of rotten Tory throwbacks. Despite the play’s crisp and convincing dialogue, it misses the cultural moment. It feels dated.

The play’s historical sections are hampered by the character of the ambitious young Heath. He proves intractable on stage. An intelligent, laconic, elusive and entirely humourless mummy’s boy, Heath never reveals himself. Nor does the play threaten his defences or present him with choices that would force him to open up. My guess is that Graham has been bewitched by late-vintage Heath, the Incredible Sulk, who glowered like a toad on the green benches for three decades.

But Heath in his heyday was refreshing and approachable. For starters, he was called Ted, like some bloke down the pub. His signature attribute was his bonhomie. Everyone in the country could impersonate him. You just had to roar with laughter and let your shoulders trampoline up and down. Compared with the shifty and neurotic Wilson, he was attractive and colourful (yachtsman, maestro), and he gave the impression of being fun to be around. But in this play Heath shows no trace of psychological complexity. He’s like Billy Bunter impersonating a cagey swat. And the script reaches puzzling conclusions about the evolution of the Tory party. If anything, it seems that life was easier for gay Tories in the past. When the closet was the only place to be, that’s where the shrewd politician stayed. And Heath had plenty of time to rehearse credible answers to tricky questions. As I recall there wasn’t much talk of his homosexuality in the 1970s. All the gossip centred on another notorious bachelor whom everyone ‘knew’ was gay: Prince Charles.

Bryony Kimmings brings her Edinburgh hit to Soho. The show opens with her on stage with her niece performing sexy duets. Kimmings strips down to a bra and spangled shorts while caressing herself suggestively. The niece, aged nine, gyrates and throws herself on her back and then flings her legs wide apart. This is intended as a ‘protest against the world’s attempt to sexualise and commodify childhood’. Right. And afterwards they strike a blow against vandalism by smashing up the theatre. The show’s kaleidoscopic range is hard to read. Bits of this and that are bunged in everywhere: sword fights, scripted banter, pious sermons, dramatic wig changes, a puppet dance, with audience participation, which is aimed at the under-threes.

Kimmings favours us with choice excerpts from her diary. She has rape fantasies, she wants a baby, she watches porn even though it’s unethical. These wordy gobbets could be improved by the addition of a punchline or two in the way that dough can be improved by the addition of yeast. After half an hour, she tells us she’s not a stand-up or an actor. She’s a performance artist. Now we’re getting somewhere. Most performance art is muddled exhibitionism constrained by nothing but the budget. Kimmings fitted snugly into this stereotype. It occurred to me that the performing niece was being exploited by her attention-seeking aunt, whose bungling script, if performed solo, would lack any semblance of moral depth.

As I left the auditorium, the gym-slip starlet was seated in the upstairs bar glowing with post-show euphoria. ‘You were brilliant,’ said a delighted punter.’ ‘Thank you,’ she twinkled. This cheered me no end. Clearly, she’s having the time of her life. Ms Kimmings, and her sister, are to be congratulated for springing the youngster from the dreary imprisonment of kiddie normality and giving her an experience that will do wonders for her confidence. And hopefully, as an adult, she’ll aim higher than performance art.