There’s plenty that’s scandalous about the Barbican’s new production of The School for Scandal, starting with the fact that director Deborah Warner rehearsed it for a full three months - longer than the show’s run.

Alan Howard (Sir Peter Teazle) and Katherine Parkinson (Lady Teazle) in The School For Scandal at the Barbican Theatre, London Photo: Tristram Kenton

It’s scandalous, too, that after all this time she should have arrived at something so provisional and unfinished - though that, of course, may be entirely the point.

The actors look like they’re floundering around, making up moves as they go along, an impression that’s established right at the beginning when the proceedings open with a witless, pointless catwalk modelling display against loud club music.

Warner is naturally thrusting the play into the here-and-now 21st century, full of romantic machinations, trysts and deceit like a slightly less poisonous Les Liaisons Dangereuses. While she was once a proponent of stripped-back but meticulous text-based drama that mined texts minutely for meaning, she now seems intent on imposing her own on the play instead. But if this aggressive display of director’s theatre comes full of baggage, she’s also added a lot of clutter to the physical space that the actors have to negotiate.

There’s a very peculiar figure who stumbles around the place, sometimes pushing a wheelbarrow, looking permanently stoned and passing out all the time. He’s the lucky one - the rest of the cast have to stay awake to fight against the concept that constantly threatens to undermine them. They include the production’s saving graces of the wonderful Alan Howard, whom it is such a pleasure to welcome back to our stages, and the brittle, brilliant Katherine Parkinson, who manage to make something both funny and true out of a marriage that has a huge age gap and is put under threat by gossip.

It’s only when the constant business (and busyness) relents and Sheridan’s own stagecraft is left to do the work in the fourth act scene of concealment in a library that the play finally works. By then, however, it’s too little, too late.