First Night: London Road, National Theatre, London

Out of tragedy is born an unlikely musical triumph

The murder of five prostitutes in Ipswich at the end of 2006, and the impact on the immediate community, might not sound like ideal material for a new musical. The mother of one of the victims has already expressed her displeasure at "making money" from the tragedy in such a way.

But London Road – the street where the convicted murderer Steve Wright, dubbed "the Suffolk strangler", rented a room for 10 weeks – is something very special indeed. It's a compassionate study in how the neighbours pull together and restore their environment around the boarded-up No 79 with tea parties and flower shows.

In one of many striking images in Rufus Norris's stunning production, the tea urn blooms into one of the resident's flower baskets and the stage is full of begonias, petunias, fuchsias and, um, those impatience things. The list is contained in the musical number, and the "um" indicates how composer Adam Cork – who wrote the songs for Enron – incorporates conversational tics and everyday inflections in his brilliant and beautiful music.

The company of 11 residents also doubles as police officers, lawyers, news reporters and the girls themselves; a trio appears in a cloud of drugs, standing stock still for what seems an age before saying they've stopped working now. It's an eerie, ambiguous moment – half in life, half in death.

All the words are the product of the verbatim theatre methods of writer Alecky Blythe, who usually has the actors fed the actual words she recorded through ear-pieces, as they deliver them. I usually find this gimmicky and distracting. But in this instance, the ear-pieces are gone and the cast, which rehearsed with the devices, merely reproduce the evidence in the performances. The result is an alive and richly flavoured text.

Blythe spent a lot of time talking to the neighbours before and after Wright's trial (he was sentenced to life imprisonment). So we get a community full of characters: the retired teachers of Rosalie Craig and Duncan Wisbey; the neighbourhood watch committee members of Clare Burt and Hal Fowler; the keen gardener and events organiser of Kate Fleetwood; the silent husband who can't get a word in edgeways; and the quiet new boy who keeps winning the competition.

They prove their solidarity best of all in the choruses and chorales, some of which are infectious "rounds" or even "serial" sequences, often set to simple phrases, like "You automatically think it could be him", or, "Did he kill them in there?"

One minute the cast is singing within a labyrinth of blue-and-white police tape, imprisoned in their own street; the next minute, the performers are lining up as rival newshounds awaiting the verdict.

The case was engrossingly dramatised last year in BBC 1's three-part drama Five Daughters, but that was a more literal and filmic approach.

This production is one of the most exciting experimental pieces the National has ever presented, and it surely marks the start of an important collaboration between Cork and Blythe.

Doubters can be assured there is no "cashing in" on the tragedy, rather a deep, abiding sadness that it happened at all, and even a slight, knowingly shameful admission that something good has come out of it: a reborn community and a renewal of civic pride in an area that became unjustly known as a red-light district when Ipswich Town left Portman Road for a new stadium elsewhere.