The musical London Road was first seen on the RNT's Cottesloe stage in 2011 before transferring to the Olivier the following year. It now reappears as a feature film – the premiere was shown via NT Live last night prior to a general release on Friday. London Road is a musical – and now a film – like none that you have ever seen before. There is a throbbing intensity throughout the piece, based on the murders of five prostitutes in the Ipswich area in 2006. Writer Alecky Blythe  specialises in verbatim work – she had visited the Ipswich area during the time of the serial killings and recorded interviews with the community showing their reaction to the tragedy unfolding around them. These are reproduced by the actors not just word for word, but inflection for inflection and pause for pause. It’s an amazingly effective technique realised in stunning detail.

The music by Adam Cork grows out of the speech almost naturally – its effect increases and creeps up on you unexpectedly. There are no 'songs' or big tunes here – it redefines the form of the musical in so many ways. Cork somehow makes a kind of melody out of the speech and speech patterns. When the music swells and edges towards the mainstream, it quickly and quietly returns to its own style again.

The central performances of a large ensemble cast include newcomers to the piece such as Anita Dobson (who coincidentally was working in panto in the area at the time of the tragedy), Olivia Coleman and the broody undertones of Paul Thornley’s Dodge. However, it’s good – and rare – to see many actors from the stage version of the piece such as Clare Burt and Linzi Hately (both of whose daughters also appear as two young inquisitive teenagers), and Claire Moore as a chirpy councillor. On stage the cast played multiple roles in this hard-to-learn piece; on screen each actor plays one part and the clarity of the storytelling is increased by making the story chronological.

The beauty of the strength of the writing is that the audience settles into the genre quickly. It’s like watching an incredibly absorbing documentary of a piece of social history, set to music. Instead of focussing on the actual murders – the five girls are only named in the context of Steve Wright’s trial results – Rufus Norris’ film keeps a firm focus on the community. This changed from fear at prostitutes working outside their homes to fear and uncertainty at the time of the murders. The community united to turn things around, planting greenery and flowers to make the area desirable again – indeed, there was a nod to this with a ‘green carpet’ for the London film premiere. This powerful, enthralling drama deserves its wider audience on the big screen – and needs to come home for another revival on stage at the RNT.