Forget Hamilton, An American in Paris is the new musical London has been waiting for

We take an exclusive look inside the technical rehearsals of An American in Paris

There's a rare level of excitement associated with the impending opening of a major new musical that's somewhat indescribable yet patently affecting. If the nervous energy, anticipation, fervour and joy could be bottled and sold it may well be labelled 'unbridled expectation with a hint of terror', but for most people who come into contact with the musical this stage of the process is difficult to imagine let alone understand.

To be invited into the 'tech' rehearsal of such a demanding and eagerly anticipated show is akin to stepping into a unique and carefully managed situation room. They say it takes a village to bring any show to fruition, but the stakes for the West End première of An American in Paris could hardly be higher or, thankfully for the production team, more enjoyable to witness.

The Dominion Theatre, benefiting from the newly found calmness of Tottenham Court Road regeneration project acts as a sort of gateway to the West End from the north, an icon of design from both inside and out. The interior has rarely looked so exposed or beautiful - its magnificent proscenium offering an unrivalled window onto the stage from across the full house, its virtues as a cinema utilised and felt from every single seat making this the perfect location for such a visually arresting production.

The auditorium remains a hive of activity and whilst it may look like a mess of wires, tables, trunks and boxes there's a careful sense of order with teams of people around the building steadily working towards the show's first public preview this weekend. The orchestra tune and play through phrases, preparing to accompany the show for only the second time since the sitzprobe whilst the costumed cast parade up and down the aisles absorbing their new home and finding a new sense of reality as the entire production gradually begins to come together.

Presenting an exclusive window into this chaotic and highly creative world allows the invited audience to understand the processes involved in bringing a musical of this size and scale to life. Audiences can rarely see or even comprehend the effort that goes into nurturing a new show to life, and despite having already been a proven hit on Broadway where it racked up an impressive 12 Tony Award-nominations the expectation is different, but certainly not lower.

The show itself starts with a solitary grand piano set against the vast bare stage, radiating opportunity and beautifully framed within the velvet tabs that hang from the proscenium adding a sense of tradition, occasion and grandeur to the visual. It's rare to see an orchestra of this size settled in the pit in their traditional location underneath the stage, the head of the conductor centre stage waiting eagerly for the first downbeat from which the intelligently moving Gershwin score unfolds.

Director-choreographer, Christopher Wheeldon is a beacon of serenity, relaxing his cast ahead of the technical run by running through notes, even jumping centre stage himself for a last minute demonstration with leading man Robbie Fairchild. For the American Ballet star and his leading lady Leanne Cope, there must be a sense of familiarity mixed with a fresh danger of performing the show in its third space since opening in Paris and at Broadway's Palace Theatre. The Dominion offers a distinctly fresh challenge with its wide open sightliness and for Cope at least, the beauty of finally performing the role on her home turf after working consistently over the past three years.

The excitement dies down as the Stage Manager calls places for the top of Act One. We're made aware of the fact that we're the first 'outsiders' to be invited to see the show and we're encouraged by Wheeldon to act like regular audience members, giving the cast a number of fresh eyes to enjoy their months of hard work and dedication.

"From the ashes of war new loves and friends are found" speaks one character as the stunning opening sequence unfolds quietly absorbing the entire stage, delighting your spirit and sending shivers down your spine. Despite the apparent slickness in this, the cast's second run, working notes are jumped on in the pursuit of perfection. In such a technically demanding production the synthesis between all creative elements has to be perfect, and for all elements of sound, movement, design and lighting to come together it's the product of hours of work and careful planning.

Having seen the show on Broadway I was prepared for Bob Crowley's arresting mise en scène that utilises some of the most ground-breaking scenic technology whilst simultaneously maintaining a tangible style that makes you want to reach out and touch as well as sit back and be transported. In the West End this style feels fresher than ever - video design has come a long way since its early use in commercial musical theatre such as Andrew Lloyd Webber's The Woman in White at the Palace Theatre back in 2004. Crowley and team blend the two worlds together so seamlessly that the set literally evolves in front of your eyes, maintaining a filmic touch against the kinetic and stylised movement that sets the tone of the whole production and raises your heartbeat.

An American in Paris demonstrates on every level what modern musical theatre has the potential to be - a fusion between the traditional and the innovative. The history of post-occupation Paris feels real as well as the feel of a country looking to come together, bond and rebuild that touches on so many wider issues within contemporary society. "People need to laugh" goes one of the opening lines in Craig Lucas' book. Audiences looking to laugh, to escape and delight in the artistry that only musical theatre can bring need look no further. From just this glimpse into a technical rehearsal you could feel the beginnings of a truly exciting piece of theatrical magic. And their journey is only just beginning...

An American in Paris tickets are now on sale for performances from 4 March 2017.