Romeo and Juliet (Garrick Theatre)

Returning to the first Shakespeare play he ever directed, Kenneth Branagh stages the Bard's love tragedy as the penultimate show in his West End season at the Garrick Theatre. Co-directed by Rob Ashford, the scene is transported from an ancient, fair Verona to a bustling, chic '50s version of Italy that is straight out of a Fellini movie. The women wear thick rimmed dark sunglasses, shawls and stilettos while the men are sharp in tailored suits, white vests and braces.

The transition works, in the main, especially because it all comes draped in a heavy Catholicism, which emphasises the high tragedy. Crucifixes hang round the necks of most of the characters and the entire piece plays out on Christopher Oram's imposing mausoleum-style set: a clever, constant reminder of where the play is headed. The mourning gets a little hysterical – especially after Tybalt is murdered – but perhaps that's rightly so: let's not forget that Romeo's mother dies from grieving.

Setting it in the '50s is not Branagh and Ashford's only twist to the play. In an inspired bit of casting, Romeo's best buddy Mercutio – usually played by an actor of similar age to Romeo – is taken on by the 77 year-old Derek Jacobi. He is Romeo and Benvolio's slightly camp, all-dancing, all-drinking, suave father figure friend. He is the life and soul of the party, swinging easily to disco music one minute while breaking into a crooning classic the next. His age brings an added poignancy to the beautiful Queen Mab speech, where the character talks of soldiers and their troubled dreams. Jacobi's Mercutio would have served in at least one of the world wars and there's clearly trauma there, bubbling below the surface.

Jacobi is infinitely watchable in a humorous, delicate way. The only problem with having him onstage is that he highlights how a lot of the cast struggle with the verse. Next to Jacobi, Richard Madden's Romeo is limp and disinteresting. Madden, a buff, quiffed ladies man – who turns into a giddy, smiling goon when he falls for Juliet – is OK, but he rushes through the text and just can't inject his speeches with any potency.

Lily James as Juliet is much better, bringing an enjoyable amount of quirky hutzpah to the role. At one point she practically downs a bottle of champagne (not bad for a girl who is not yet 14) and she imbues her speeches with vigour and passion. Meera Syal is funny as Nurse, but again, when she speaks the verse it sounds oddly clunky. There's a strong turn from Michael Rouse as Lord Capulet, who is all frightening ticks and bursting anger. He frequently betrays himself: the rough, intimidating gang boss breaks through the veneer of respectability.

The show rushes through the 'two hours' traffic', steaming ahead without looking back. But this Romeo and Juliet works best when it lingers, and really in this cast it is only in Jacobi's all too fleeting moments that the play is brought vividly to life.

Romeo and Juliet runs at the Garrick Theatre until 13 August.