The curtain could finally be raised on a forgotten 400-seat underground theatre beneath Islington Green – a decade after it was built.

Islington Gazette: An artist's impression of how the theatre could look. Picture: Foster Wilson ArchitectsAn artist's impression of how the theatre could look. Picture: Foster Wilson Architects (Image: Archant)

The £35million Collins Theatre, under the old Collins Music Hall – now Waterstones – was constructed as an Elizabethan courtyard-style venue and was originally meant to have the salvaged set from Shakespeare in Love as its auditorium.

The plans were initially signed off in 2002 and included building 72 flats to pay for the theatre. Designers decided the only way to fit the planned 600-seater veune into the site was to dig down three storeys – and 22 metres.

However, a row between the previous owners – a trust headed up by the Old Vic’s then chief exec Sally Greene – and the developers, as well as various planning complications, stopped the project in its tracks.

The flats are there, but the theatre has been left in shell form since it was finished in 2008.

The ambitious designs for the theatre included having a public piazza above it. The glass canopy that was to cover the piazza can be seen spilling over a temporary wall in Essex Road today.

Now, at last, things are looking up. Developer Berjaya UK Investment and Development has submitted plans following discussions with the Theatres Trust to finally open the space.

The company has also worked with unknown firm Shawthing Productions on a management plan for the venue.

The theatre capacity would now be 400, with a separate “Food Village” outlet for small street food outlets and a bar fronting onto Islington Green.

Islington Gazette: An artist's impression of how the theatre could look. Picture: Foster Wilson ArchitectsAn artist's impression of how the theatre could look. Picture: Foster Wilson Architects (Image: Archant)

Should the scheme come off, it would put an end to an exhausting saga that started with a straightforward campaign to replace a lost treasure.

The Collins Music Hall was opened in 1863 by entertainer Sam Collins at the rear of The Landsdowne Arms pub and seated up to 1,000 people.

Collins died two years after the launch and in 1897 a syndicate redesigned the venue.

Charlie Chaplin, Tommy Cooper, Norman Wisdom and Benny Hill all played the theatre, but in 1958 it was gutted in a fire that destroyed all but the front and side walls.

Islington Gazette: An artist's impression of how the theatre could look from Upper Street. Picture: Foster Wilson ArchitectsAn artist's impression of how the theatre could look from Upper Street. Picture: Foster Wilson Architects (Image: Archant)

Avid Saltsman Baldry was chair of the Anderson’s Yard Campaign from 1991 to 1997, when the group folded. It had formed in 1989 to fight plans for another office block near The Angel, but its principal aim became a replacement theatre for the music hall.

Avis, now in her 80s, told the Gazette last week she never expected to see it open after all this time.

“It would be amazing,” she said. “I had given up hope but it would be wonderful if it happened.”

Avis spoke at the original planning meeting and was one of the lucky few who got to go on a tour of the theatre when it was completed.

“That was a very long time ago,” she added. “But it was an amazing space that could be used for various things.

“The idea back then was for there to also be things for children, to get them interested in theatre.”

It is not known if that is still the case, but the plans have changed numerous times since they were initially signed off.

Conditions attached to the original approval stated that no more than 85 per cent of the flats could be sold until the theatre work had started and that £2.17m must be spent on the theatre project – for the shell and the fitting out – within six months. If the latter did not happen, the developers were to pay the council the difference within a year.

The Collins Theatre Trust – led by Greene and her property developer husband Robert Bourne – was behind the scheme, which had no public funding. But developer Frasers Islington ran into complications fitting out the theatre. Eventually planning permission was sought, and approved, allowing all of the flats to be sold before the completion of the venue.

When the shell was finished in 2008 work stopped, although it has been used for a One Direction music video, a Red Bull event, a Skepta gig and, earlier this year, a one-off theatre production.

In 2009 the Collins Theatre Trust became involved in a High Court battle with Frasers over the handing over of keys and the opening was put on hold. The Collins Theatre Trust was eventually dissolved in 2015.

Then, in 2016, an application for a 400-seat theatre and two studio spaces was given the green light by Islington, but negotiations to find an operator failed and it was back to the drawing board for all involved.