IT isn't immediately clear what's going on behind the big wooden double doors that lead into Scottish Opera's Glasgow rehearsal room. Inside, Vanishing Point theatre company director Matthew Lenton is rehearsing his production of The 8th Door, a devised work created with Scottish Opera composer Lliam Paterson in a co-production between the two companies that marks Lenton and Vanishing Point's first foray into opera. The 8th Door forms the first part of a double bill with Bluebeard's Castle, composer Bela Bartok and librettist Bela Balazs' blood-soaked one-act work, which was first performed in 1918.

Outside, in the corridor, all that can be gleaned comes from a dissonant orchestral blare that seeps through the pitch-black that can be seen through the crack left between the doors. Once the music stops and the lights go on, things become more familiar. Two large screens are fixed at one end of the room, onto which are projected the close-up the faces of actors Elicia Daly, Pauline Goldsmith and then Gresa Pallaska as they sit side by side beneath the screen. As the recorded music plays, it is as if some approximation of an expressionist silent movie is being played out. Without a word being spoken, the expressions on the faces of Daly, Goldsmith and Pallaska hint at shared anxieties and things left unsaid.

It's the week before Christmas 2016, and, as is ever the case with Vanishing Point, a company that has developed a globally acclaimed canon over the last decade with shows such as Interiors and, more recently, The Destroyed Room, this new show, set to be premiered in late March, doesn't quite know what it is yet.

“These two weeks are about trying to find a physical language to go with the music of the piece that Lliam has written,” Lenton says of The 8th Door. “This is really us trying to get the form that we think we should be working with, interrogating that, and setting ourselves certain challenges that test how we visualise this piece of music.

“In terms of the fiction of the piece, the music came first, so that's a different way of working for me. Lliam has written this independent piece of work that reflects Bluebeard's Castle, so I'm thinking of this as both a stand-alone work and an introduction to the second part of the evening when we actually do Bluebeard's Castle.”

Bartok and Balazs's work was written in Hungarian and based on the French story, La Barbe bleue by Charles Perrault. With Bluebeard and his new wife Judith the only two singing characters onstage, Bluebeard is forced by his new bride to give a guided tour of their new home in order to let in some light. What each room reveals opens up a psycho-sexual voyage into Bluebeard's inner turmoil. The 8th Door may precede it, but, in keeping with Lenton and Vanishing Point's own leaps into the dark, couldn't be described as a prequel in any conventional narrative sense.

“In The 8th Door we're seeing the surface of two people and the way they behave towards each other,” says Lenton, “and we're beginning to notice the fractures that are beginning to open up in that relationship. It's almost as if its through one of those fractures that Judith and Bluebeard have fallen, which is this subterranean subconscious world.

“In that sense, the two pieces are counterpoints to each other, in that one is on the surface, broadly speaking, and is inviting the audience to guess what might be deeper. Bluebeard's Castle, on the other hand, exists in this dream-world, where two people find themselves within each other's subconscious, or within one subconscious if you like.

“The last line in the libretto of The 8th Door is something about how there are no two things that are further apart than human souls, so it's a really simple journey about two people who have an emotional connection with each other, but which slowly and traumatically comes apart. This leaves the woman in particular in a position where she wants to confront this thing that's happened, and that becomes the compulsion for her to enter this subconscious world of Bluebeard's Castle.”

The libretto of The 8th Door features texts by Hungarian poets and lesser known contemporaries of Bartok including Endre Ady and Attila Jozsef. These come in translations by the former Scottish makar, the late Edwin Morgan.

“I'm a big fan of Edwin Morgan,” says Paterson, “and wrote a song cycle based on his poetry shortly before starting this project. I just happened to come across his translations of Hungarian poets, so there was a nice link there, especially when it transpired that Endre Ady and Attila Jozsef both knew Bartok and Balazs, and were part of the same artistic and social circles in Budapest. The themes of isolation and alienation in their work seemed to be very much on the same page as Bluebeard's Castle, which is one of my favourite operas, and it was fascinating finding all of these deep connections with Bartok.”

The piece will be performed by Daly, Goldsmith and Pallaska alongside Robert Jack. All four actors will appear in Bluebeard's Castle, with Karen Cargill and Robert Hayward singing the lead roles. In The 8th Door, the actors will be supported by six singers and the Orchestra of Scottish Opera, conducted by Sian Edwards.

“The 8th Door is more a piece of musical theatre than an opera, and the singers are in the pit with the orchestra,” says Paterson. “I don't just have the singers singing in a conventional operatic way. They can whisper because they're amplified, and there are certain sonic gestures that are set up initially by Bartok which foreshadow some of the things we do in The 8th Door.”

In one sense, opera is a natural move for Lenton, whose work has consistently begun with visual motifs, with music forming a key part of what are more dramatic tone poems than plays per se. Such a blurring of forms is inherent in Lenton's work.

“I think what I'm interested in by using this kind of form is trying to create something that's musical in itself,” he says, “so what we're watching has a musicality to it. I'm interested in how, even though we're using this big operatic music, what we're watching is small things, tiny details. You associate opera with big physical movements and grandiose gestures, but in The 8th Door we're doing the opposite. It's about how we can connect the music with things that are very fragile, delicate and almost microscopic. That way, the audience can go along with it, and enter the subconscious world that it conjures up.”

The 8th Door and Bluebeard's Castle, Theatre Royal, Glasgow, March 28, 30 and April 1; Festival Theatre, Edinburgh, April 5 and 8.

www.scottishopera.org.uk

www.vanishing-point.org