Director Michael Grandage conjures up an almost magical Illyria, drenched in sunshine. This is a Twelfth Night as imagined by PG Wodehouse, with a glorious 30s setting, and rich on the interplay between the aristocracy and their servants. Derek Jacobi's Malvolio, dripping with unctuousness, is the epitome of servility – while at the same time dreaming of a place amongst his betters.

The eavesdropping scene is played to perfection, the three plotters (Fabian has been dropped from the play) being forced to stuff their handkerchiefs in their mouths from laughter as Malvolio is drawn into their trap and the last image before audiences troop off to the interval is seeing Jacobi trying to wrest a smile from his lips, a struggle for a man after a lifetime of seriousness.

The class aspect is extremely well-played, with all characters fully aware of their positions in society – positions that become considerably disrupted in the course of the play.

“Art any more than a steward?” sneers Sir Toby, finding it hard to keep the contempt from his voice. Ron Cook's Toby is less the drunken sot than is usual and presents himself as a man acutely aware of his place in society and the privilege of being Olivia’s uncle. If he underplays the comedy slightly, this is more than made up by Guy Henry's Andrew Aguecheek, a gawky, slack-jawed streak of idiocy, an Illyrian cousin to Bertie Wooster, who provides most of the best comic moments.

But while Grandage brings out the comedy and the underlying conflicts of class, he is less successful in tackling the sexual ambiguity in the play. I wasn’t convinced by Victoria Hamilton’s Viola, who doesn’t seem to make the most of the confusion engendered by her transformation into Cesario.

And I was also left confused by Mark Bonnar's Orsino, one minute, unkempt and half-dressed bewailing his love for Olivia, the next dancing with his male entourage – leaving one wondering why exactly he wants to woo Olivia. There is however a great moment in the final scene when he mistakes Sebastian for Viola one last time. In contrast to the Orsino court, the homoerotic relationship between Antonio and Sebastian seems rather under-played, leaving us rather unsure exactly why Antonio puts himself in such peril.

I did however like Indira Varma’s Olivia, hastily casting off her mourning demeanour in pursuit of Cesario and her delighted “how wonderful” when seeing the twins for the first time was the cry of a woman well alive to sexual possibilities.

Perhaps most joyous of all, this is a very funny production. The sun-drenched Adriatic might not sound like an ideal setting for a Christmas play but this is festive fun and should prove a huge hit.

- Maxwell Cooter