Cy Coleman’s jazz musical City of Angels – enjoying a sell-out run at the Donmar Warehouse – is a clever and slick production, with the action switching seamlessly between two worlds. Set in Hollywood during the 1940s glamour era of the silver screen, Hadley Fraser is Stine, a disillusioned writer who is penning a screenplay that features a fictional private eye Stone (Tam Mutu). The audience see both Stine’s real-life story and Stone’s fictional one.

As Stine writes in his studio on an upper platform against a stunning backdrop of books and scripts, lit in colour, the black and white action of the film studio is seen below. In some scenes, as Stine types the words appear simultaneously on a narrow one-line screen with the film action created in front of our eyes underneath – some of his rewrites are even shown in slow motion backwards.

The two worlds becomes even more intertwined as the story goes on, with four leading ladies taking dual roles in both worlds. Rebecca Trehearn’s big number ‘You Can Always Count On Me’ starts in black and white as Stone’s secretary Oonie, before the lighting changes to colour as she sheds her coat to reveal a brightly coloured dress as the film director’s secretary Donna. In an eye-catching performance, Trehearn cleverly vocally differentiates between the two characters too.

Katherine Kelly is a real femme fatale, as Alaura Kingsley who initiates the ‘who is deceiving who’ detective story. Dressed in glamorous fur, Kelly has a great physicality in the way she moves, smokes and stares. ‘The Tennis Song’ duet with Stone is both ironic and iconic. And Samantha Barks channels a young Marilyn Monroe as her stepdaughter Mallory.

But it’s the two leading men, Stine and Stone, who are at the heart of the action throughout. Hadley Fraser sings like a dream as Stine battles between the integrity of his art and what director Buddy Fidler (a deliciously egotistic Peter Polycarpou) and the studio demand of him. He has the perfect equal in Tam Mutu’s Stone, the ‘fictional’ detective who gets himself into some shady situations. Their Act 1 finale ‘You’re Nothing Without Me’ is a real battle of wills – a central line is drawn down the middle of the stage, with Howard Harrison’s innovative lighting design gradually moving the boundaries in colour or black and white as one of them gains ground on the other.

A quartet called ‘The Angel City Fours’ flit in and out of the action in gloriously choreographed movements by Stephen Mear, often moving scenery on and off the compact Donmar stage. All have fabulously rich jazz voices, ideal for this, Cy Coleman’s jazziest score. Coleman was a jazz pianist at heart, and this score – with witty lyrics by David Zippel – is surely one of his finest. Rosalie Craig gets some good numbers as Stine’s long-suffering wife Gabby, and her duet with Trehearn ‘What You Don’t Know About Women’ is an early highlight. But this is an evening of highlights, with a succession of strong numbers all well acted and performed. It all adds up to an incredible vision for Donmar artistic director Josie Rourke’s first musical.